motorboat action meaning

What is the meaning of the term 'motorboating' and what is its origin?

The term "motorboating" has two distinct meanings.

The first meaning refers to the activity of traveling in a motorboat [2] . This is the literal definition of the term and is commonly used in the context of recreational boating or water sports.

The second meaning, which is more commonly known as slang, refers to a sexual act. It involves placing one's face between a woman's breasts and making a noise like a motorboat by rapidly moving one's head from side to side [1] [2] . This slang term is often used humorously or in a playful manner.

Origin: The origin of the term "motorboating" in the context of the sexual act is not well-documented. However, it is believed to have emerged as a slang term in popular culture, possibly in the late 20th century or early 21st century. The act itself is a playful and humorous gesture, and the term likely originated as a way to describe the sound and motion made during the act, which resembles the noise and movement of a motorboat.

Learn more:

• What does motorboating mean? How did the term originate?
• motorboating - Wiktionary, the free dictionary
• Where did the term motorboat come from? | AnandTech Forums: Technology, Hardware, Software, and Deals

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How Electric Motors and Generators Work

Learn How They Generate Power for Electric Cars & Hybrids

Christine and Scott Gable are hybrid auto and alternative fuel experts who have brewed their own biodiesel and traveled 125,000 miles on waste vegetable oil.

• Millersville University
• Public Transportation

Electric vehicles rely exclusively on electric motors for propulsion, and hybrids use electric motors to assist their internal combustion engines for locomotion. But that's not all. These very motors can be, and are, used to generate electricity (through the process of regenerative braking ) for charging these vehicles' onboard batteries.

The most common question is: "How can that be ... how does that work?" Most folks understand that a motor is powered by electricity to do work—they see it every day in their household appliances (​washing machines, vacuum cleaners, food processors).

But the idea that a motor can "run backward," actually generating electricity rather than consuming it seems almost like magic. But once the relationship between magnets and electricity (electromagnetism) and the concept of conservation of energy is understood, the mystery disappears.

Electromagnetism

Motor power and electricity generation begin with the property of electromagnetism—the physical relationship between a magnet and electricity. An electromagnet is a device that acts like a magnet, but its magnetic force is manifested and controlled by electricity.

When wire made of conducting material (copper, for example) moves through a magnetic field, current is created in the wire (a rudimentary generator). Conversely, when electricity is passed through a wire that is wound around an iron core, and this core is in the presence of a magnetic field, it will move and twist (a very basic motor).

Motor/Generators

Motor/generators are really one device that can run in two opposite modes. Contrary to what folks sometimes think, that does not mean that the two modes of the motor/generator run backward from each other (that as a motor the device turns in one direction and as a generator, it turns the opposite direction).

The shaft always spins the same way. The "change of direction" is in the flow of electricity. As a motor, it consumes electricity (flows in) to make mechanical power, and as a generator, it consumes mechanical power to produce electricity (flows out).

Electromechanical Rotation

Electric motor/generators are generally one of two types, either AC (Alternating Current) or DC (Direct Current) and those designations are indicative of the type of electricity that they consume and generate.

Without getting into too much detail and clouding the issue, this is the difference: AC current changes direction (alternates) as it flows through a circuit. DC currents flow uni-directionally (stays the same) as it goes through a circuit.

The type of current utilized is concerned mostly with the cost of the unit and its efficiency (An AC motor/generator is generally more expensive, but is also much more efficient). Suffice it to say that most hybrids and many larger all-electric vehicles use AC motor/generators—so that is the type we'll focus on in this explanation.

An AC Motor/Generator Consists of 4 Main Parts:

• A shaft-mounted wire wound armature (rotor)
• A field of magnets that induce electrical energy stacked side-by-side in a housing (stator)
• Slip rings that carry the AC current to/from the armature
• Brushes that contact the slip rings and transfer current to/from the electrical circuit

The AC Generator in Action

The armature is driven by a mechanical source of power (for example, in commercial electric power production it would be a steam turbine). As this wound rotor spins, its wire coil passes over the permanent magnets in the stator and an electric current is created in the wires of the armature.

But because each individual loop in the coil passes first the north pole then the south pole of each magnet sequentially as it rotates on its axis, the induced current continually, and rapidly, changes direction. Each change of direction is called a cycle, and it is measured in cycles-per-second or hertz (Hz).

In the United States, the cycle rate is 60 Hz (60 times per second), while in most other developed parts of the world it is 50 Hz. Individual slip rings are fitted to each of the two ends of the rotor's wire loop to provide a path for the current to leave the armature. Brushes (which are actually carbon contacts) ride against the slip rings and complete the path for the current into the circuit to which the generator is attached.

The AC Motor in Action

Motor action (supplying mechanical power) is, in essence, the reverse of generator action. Instead of spinning the armature to make electricity, current is fed by a circuit, through the brushes and slip rings and into the armature. This current flowing through the coil wound rotor (armature) turns it into an electromagnet. The permanent magnets in the stator repel this electromagnetic force causing the armature to spin. As long as electricity flows through the circuit, the motor will run.

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• Published: 01 September 2001

Neurophysiological mechanisms underlying the understanding and imitation of action

• Giacomo Rizzolatti 1 , 2 ,
• Leonardo Fogassi 1 &
• Vittorio Gallese 1  

Nature Reviews Neuroscience volume  2 ,  pages 661–670 ( 2001 ) Cite this article

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What are the neural bases of action understanding? Although this capacity could merely involve visual analysis of the action, it has been argued that we actually map this visual information onto its motor representation in our nervous system. Here we discuss evidence for the existence of a system, the 'mirror system', that seems to serve this mapping function in primates and humans, and explore its implications for the understanding and imitation of action.

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A sensory–motor theory of the neocortex

Delineating visual, auditory and motor regions in the human brain with functional neuroimaging: a BrainMap-based meta-analytic synthesis

Action execution and action observation elicit mirror responses with the same temporal profile in human SII

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Positron emission tomography

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Attribution theory

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A variant of the transcranial magnetic stimulation technique, in which two coils are used to generate magnetic fields in quick succession over the same cortical region or in different regions at the same time.

Also known as the Hoffmann reflex, the H reflex results from the stimulation of sensory fibres, which causes an excitatory potential in the motor neuron pool after a synaptic delay. Exceeding the potential threshold for a given motor neuron generates an action potential. The resulting discharge will cause the muscle fibres innervated by that neurone to be activated.

A movement not directed towards an object.

A disorder characterized by facial paralysis, attributed to defects in the development of the sixth (abducens) and seventh (facial) cranial nerves.

A philosophical movement founded by the German Edward Husserl, dedicated to describing the structures of experience as they present themselves to consciousness, without recourse to theory, deduction or assumptions from other disciplines, such as the natural sciences.

Stimuli devised by the Swedish psychologist Johannson to study biological motion without interference from shape. Light sources are attached to the joints of people and their movements are recorded in a dark environment.

A technique used to stimulate relatively restricted areas of the human cerebral cortex. It is based on the generation of a strong magnetic field near the area of interest which, if changed rapidly enough, will induce an electric field sufficient to stimulate neurons.

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Rizzolatti, G., Fogassi, L. & Gallese, V. Neurophysiological mechanisms underlying the understanding and imitation of action. Nat Rev Neurosci 2 , 661–670 (2001). https://doi.org/10.1038/35090060

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Apraxia is a neurological disorder that affects motor cognition, planning, and task performance without apparent neurological insult to basic motor function, sensation, or comprehension. This disorder can result from various types of brain lesions, including stroke, dementia, tumors, neurocognitive disorders, and brain injuries. Identifying and diagnosing apraxia primarily relies on clinical assessment, lacking broad consensus on methods and definitions. Understanding the relevant neuroanatomy and conducting a comprehensive physical examination are crucial for evaluating and managing the condition. Treatment modalities involve managing the underlying disorder and implementing associated supportive measures. Early identification of apraxia can significantly enhance the patient's ability to perform activities of daily living.

This activity comprehensively reviews the etiology, pathophysiology, clinical assessment, evaluation, treatment, and complications of apraxia. This activity also emphasizes the integral role of the interprofessional healthcare team in evaluating and treating patients with this condition. This activity offers strategies for fostering effective communication and collaboration among multidisciplinary healthcare team members involved in apraxia care, thereby optimizing patient outcomes. 

• Identify the signs and symptoms of apraxia across diverse patient populations and clinical settings.
• Implement evidence-based interventions tailored to the specific needs and abilities of patients with apraxia.
• Select appropriate assistive devices and technologies to support patients with apraxia in their daily activities.
• Collaborate with occupational therapists, speech-language pathologists, and other healthcare professionals to provide comprehensive care for patients with apraxia.
• Introduction

Apraxia is the inability to perform skilled movements, whether they have been previously learned or can be immediately imitated by observing or carrying out the instructions of another individual. [1] [2] Diagnosis involves ruling out weakness, sensory dysfunction, comprehension deficits, or incoordination as potential causes. [1] [2] [3] Initially, Hugo Karl Liepmann classified apraxia into 3 types—limb-kinetic, ideomotor, and ideational. [4] Liepmann's descriptions laid the groundwork for today's characterizations. However, the concept of apraxia now comprises a broader spectrum of subtypes compared to those originally identified by Liepmann. Broadly, apraxia can be classified based on specific tasks performed or general actions taken. [5] Unfortunately, the subtypes of apraxia are not defined consistently in the literature. [6]

Major forms of apraxia are listed below.

• Ideational: Loss of neural encoding of the concept of a previously known skill
• Ideomotor: Impaired connection between the concept of a skill and its motor output
• Limb-kinetic: Loss of the motor output associated with a given skill
• Conceptual: Loss of ability to use tools
• Specific constructional: Difficulty in drawing, constructing, or copying

The term "ideational apraxia" is sometimes alternatively used to describe the loss of the ability to perform a sequence of movements. In contrast, "conceptual apraxia" refers to the loss of the concept itself. [2] [6]  However, a thorough discussion of usage differences is beyond the scope of this article.

Praxis, or the ability to carry out skilled actions, involves the activation or inhibition of neural networks in the brain. The type of apraxia manifested can vary depending on the involved neural network. [3]  Apraxia can be diagnosed by performing a comprehensive examination on patients, which includes a detailed history, neurological examination, and apraxia-specific testing. However, consensus on the best operational practices for assessing apraxia does not exist. [1]

The management of apraxia involves addressing its underlying causes through physical, occupational, or other task-specific therapies, alongside counseling. Long-term outcomes depend on the type of apraxia and its effect on the patient's activities of daily living. Associated deficits can vary from acalculia, agraphia, and aphasia to confusion, social anxiety, and low self-esteem. Some individuals with apraxia may necessitate long-term assisted nursing care.

Some of the known causes of apraxia include:

• Corticobasal syndrome  [8]
• Alzheimer disease  [9]
• Huntington disease
• Multiple sclerosis  [10]
• Tumors  [11]
• Creutzfeldt-Jakob disease  [12]
• Schizophrenia
• Traumatic brain injury  [13]

The risk of developing a specific form of apraxia depends on the risk of developing its associated etiological disorder.

• Epidemiology

Apraxia is prevalent in approximately 50% to 80% of individuals with left hemisphere strokes, 30% to 50% with right hemisphere strokes, 19% to 45% with traumatic brain injuries, 25% with multiple sclerosis, and 90% with dementia. [14] [15]  However, population-level incidence and prevalence data for apraxia are unfortunately limited.

• Pathophysiology

Praxis has various conceptual subdivisions. One example is its subdivision into the use of objects or tools and the performance of gestures, either by imitation or on command. [16] Although the neural networks subserving different types of praxis are nonidentical, specific brain structures, such as the left inferior parietal lobule and frontal motor areas, are involved in praxis and apraxias. [16] [17] [18] [19]

A typical schema for the structures involved in praxis illustrates that praxis networks can be activated through visual, auditory, verbal, or tactile stimuli. The activated sensory modality provides information to neurons in the left parietal lobe, which selectively fires to commence the praxis process. [20] [21]  Subsequently, there is feedforward to the supplementary and premotor areas, where corresponding maps of coordinated movements are accessed. This information is sent to the primary motor cortex, which initiates the encoded motor programs by activating the musculature through the pyramidal tracts. [2]

Models of praxis and its associated networks are continually evolving. Additional structures are implicated, including the thalami, basal ganglia, prefrontal regions, temporal regions, and connecting white matter. Damage to these structures, which constitute the praxis networks, can result in apraxia, depending on the role of the damaged structure within its network. [2]

• History and Physical

Evaluation of apraxia can begin after a comprehensive neurological examination, which excludes sensory, motor, and cognitive dysfunction as potential causes of the observed deficits. Before testing, the patient must first demonstrate an understanding of and ability to execute the tasks used for testing. Although there is no prescribed sequence for testing limbs, both sides should undergo evaluation. [2] [22]

In general, 2 types of actions are assessed—those that are directly imitated and those that are recalled from memory. These actions can be further subdivided into 3 categories—intransitive gestures, transitive gestures, and pantomime of tool use. Intransitive gestures, also known as symbolic gestures, do not depend on using an object, such as saluting or waving goodbye. Transitive gestures involve using an object, such as swinging a hammer or flipping a coin. Pantomime involves mimicking or simulating the use of tools or objects without them being physically present. In addition, meaningless gestures, such as holding the thumb to the underside of the nose, can also be assessed. [2] [22]

Examples of abnormal findings associated with apraxia subtypes are listed below. [2]

• Ideomotor apraxia: Patients exhibit an inability to pantomime or imitate gestures. Moreover, they experience challenges with spatiotemporal orientation and positioning. Movements involving their fingers, hands, and arms display abnormal trajectories. 
• Ideational apraxia: Patients struggle to identify the correct sequence of actions necessary to accomplish a task. Even when provided with a list of required steps, they may encounter difficulties organizing them accurately.
• Limb-kinetic apraxia: Patients exhibit incorrect fine motor actions, particularly with their hands, when attempting to perform a learned task. For instance, they may struggle with rotating a coin using their thumb, index finger, and middle finger.
• Conceptual apraxia: Patients face challenges identifying the appropriate tool for a given task. When presented with a tool, they may struggle to discern its purpose. Additionally, they may experience difficulty in pantomiming the correct utilization of a tool.

Formal testing tools for limb apraxia include the Florida Apraxia Battery–Extended and Revised Sydney (FABERS), the Apraxia Battery for Adults-2, the Short Screening Test for Ideomotor Apraxia (STIMA), the Cologne Apraxia Screening (KAS) or Revised Cologne Apraxia Screening (KAS-R), the Diagnostic Instrument for Limb Apraxia (DILA) or the Diagnostic Instrument for Limb Apraxia-Short Version (DILA-S), and the Test of Upper Limb Apraxia (TULIA). [23] [24] [25] [26] [27]

Thorough assessment methods, including detailed history-taking, physical examination, and neuropsychological testing, are used to identify and classify apraxia. Additional testing is used not to describe the apraxia further but to determine its etiology. Apraxia may develop acutely after a neurological insult such as stroke or traumatic brain injury. Alternatively, it may also be insidious, as observed in neurodegenerative disorders. Patients are often unaware of their inability to perform previously learned skills and activities.

Radiological and laboratory evaluation of apraxia can assist in uncovering etiologies associated with apraxia, including cerebrovascular disease, neurodegenerative disorders, traumatic brain injury, tumors, and multiple sclerosis. Imaging modalities such as magnetic resonance imaging (MRI) and positron emission tomography (PET) can identify associated brain lesions.

• Treatment / Management

The primary treatment for apraxia involves focused rehabilitation utilizing various therapies such as occupational, speech, and physical, alongside addressing the underlying disorder. Apraxia can significantly impair independent functional capacity, with its presence often indicating the level of caregiver assistance needed post-stroke, while its absence may predict an early return to work. [28]

Currently, a widely accepted treatment strategy for apraxia does not exist. The challenge of creating task-specific therapies with generalizable benefits is illustrated in the work of Buxbaum et al. [29] Rehabilitation is ideally initiated promptly following apraxia diagnosis, particularly in cases stemming from acute lesions. [30] [31] Newer technologies, such as transcranial magnetic stimulation, have shown promise in treating apraxia. [32]

• Differential Diagnosis

Several disorders related to movement or speech can be mistaken for apraxia, such as aphasia, nonapraxic dysarthria, alien limb phenomenon, akinesia, magnetic grasp, grope reflex, motor preservation, and motor impersistence.

Patients with apraxia can have significant issues with performing learned skills, which can profoundly affect their independence and ability to carry out activities of daily living. Appropriate safety precautions must be implemented with objects and activities in their surroundings that can cause potential injury. In cases where the inability to perform certain learned skills is debilitating, patients may require skilled nursing care. The eventual prognosis varies depending on the patient and the underlying etiological disease. 

• Complications

Potential sequelae of apraxia include:

• Inability to perform activities of daily living
• Failure to function properly at work
• Injury caused by improper tool use
• Social isolation
• Social anxiety
• Low self-esteem
• Deterrence and Patient Education

The most common causes of apraxia include stroke, dementia, and traumatic brain injury. Apraxia is often a sign of a complex underlying neurological condition that poses challenges in its management. Education regarding modifiable risk factors should be prioritized whenever possible. Pharmacological interventions and lifestyle management addressing hypertension, diabetes mellitus, sleep apnea, atrial fibrillation, tobacco use, and alcohol consumption can contribute to better outcomes.

Regardless of the underlying causes, the inability to perform specific tasks due to apraxia can evoke frustration, potentially resulting in loss of capacity, diminished motivation, depression, and further deterioration of function. Educational resources, effective communication with caregivers, and counseling of family members can be crucial in establishing realistic expectations, understanding care goals, and anticipating the challenges in the recovery journey. Active participation by patients, caregivers, and family members can significantly facilitate the rehabilitation process.

• Pearls and Other Issues

Key facts to keep in mind about apraxia include:

• Apraxia is a neurological disorder characterized by the inability to perform learned or purposeful movements.
• Types of apraxia include ideomotor, ideational, limb-kinetic, and conceptual forms.
• Common causes of apraxia include stroke, traumatic brain injury, dementia, neurodegenerative disorders, tumors, and schizophrenia.
• Although occupational, physical, and speech therapy may help improve functional impairments caused by apraxia, addressing the underlying cause is necessary.
• The prognosis depends on the underlying cause and promptness of intervention.
• Enhancing Healthcare Team Outcomes

Apraxia poses a challenge for clinicians due to the complexity of its identification and testing. The presence of concurrent neurological and psychological factors can obscure symptoms. Causes of apraxia range from acute disorders such as stroke and traumatic brain injury to chronic conditions such as neurodegenerative illness or schizophrenia. Furthermore, it can be mistaken for neurological conditions such as aphasia, abulia, and limb akinesia. 

The lack of broad consensus concerning screening and diagnosis can frustrate healthcare providers. However, a detailed history, physical examination, and targeted testing can facilitate early identification and management. Despite inconsistencies in subtype definitions, healthcare professionals prioritize a multidisciplinary approach to diagnosing and managing apraxia, emphasizing seamless communication and collaboration within the healthcare team, thereby gaining valuable insights into the complexities of diagnosing and managing the condition.

The involvement of multidisciplinary and interprofessional teams is paramount in managing apraxia to enhance patient outcomes. This team can include the patient, their family members, nurses, occupational therapists, physiotherapists, primary care physicians, radiologists, neurologists, physiatrists, psychiatrists, counselors, social workers, and case workers. Each healthcare team member should maintain open communication channels with the rest of the team and be responsible for maintaining accurate and detailed records of interactions, interventions, and testing. Such an interprofessional approach significantly enhances patient outcomes.

In both inpatient and outpatient settings, a primary care physician or neurologist can assess for apraxia through comprehensive examination and history-taking. Nurses caring for patients can identify deficiencies in limb function, tool usage knowledge, and general demeanor alterations. Family members can aid in identifying patient weaknesses while they undergo rehabilitation. Therapists can assist in improving limb function and help patients acquire new skills for limb and tool usage. Psychological support during the recovery and rehabilitation phases is vital for long-term patient well-being. 

Establishing a supportive environment at home and work for the patient's condition can facilitate their recovery process. The long-term outcome depends on the etiology and duration of the illness. However, prompt identification and management of the condition by an interprofessional healthcare team can lead to an improved prognosis.

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Disclosure: Supreeth Gowda declares no relevant financial relationships with ineligible companies.

Disclosure: Brendan Hodis declares no relevant financial relationships with ineligible companies.

Disclosure: Lynne Kolton Schneider declares no relevant financial relationships with ineligible companies.

This book is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ), which permits others to distribute the work, provided that the article is not altered or used commercially. You are not required to obtain permission to distribute this article, provided that you credit the author and journal.

• Cite this Page Gowda SN, Hodis B, Kolton Schneider L. Apraxia. [Updated 2024 May 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

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• Review Apraxia: Review and Update. [J Clin Neurol. 2017] Review Apraxia: Review and Update. Park JE. J Clin Neurol. 2017 Oct; 13(4):317-324.
• Callosal apraxia. [Brain. 1983] Callosal apraxia. Watson RT, Heilman KM. Brain. 1983 Jun; 106 (Pt 2):391-403.
• Review Limb apraxias: higher-order disorders of sensorimotor integration. [Brain. 2000] Review Limb apraxias: higher-order disorders of sensorimotor integration. Leiguarda RC, Marsden CD. Brain. 2000 May; 123 ( Pt 5):860-79.
• Review Hugo Liepmann, Parkinson's disease and upper limb apraxia. [Cortex. 2020] Review Hugo Liepmann, Parkinson's disease and upper limb apraxia. Heilman KM. Cortex. 2020 Oct; 131:79-86. Epub 2020 Jul 21.
• Review Apraxia: neural mechanisms and functional recovery. [Handb Clin Neurol. 2013] Review Apraxia: neural mechanisms and functional recovery. Foundas AL. Handb Clin Neurol. 2013; 110:335-45.

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• A-Z of motor boats: your ultimate guide

Motor boats don't often take centre stage in our magazine, but we're about to change that. This in-depth feature explores the different kinds of motorboats, their manufacturers, how they differ from sailboats, and weighs their pros and cons. We'll help you figure out if a motorboat is the right fit for you, when to best venture out on one, and we'll delve into the requirements and conditions for a skipper's licence. In essence, we're bringing you the complete motorboat rundown. All hail the engine!

Differences to a sailboat

The age-old debate of powerboat versus sailboat is a classic theme in many a nautical conversation. We're not here to pick a side between those who favour sails and those who prefer motors. Instead, our aim is to present you with a balanced view, packing all the necessary facts, insights, and knowledge into one comprehensive discussion.

Draft and bridges

A motorboat's draft is significantly shallower, thanks to the absence of a keel. Furthermore, the lack of a mast means there's no need to worry about the boat's height when it comes to passing under bridges. So from a depth and overhead clearance perspective, you're in safe waters with a motorboat.

YACHTING.COM TIP: If you've never sailed under the renowned Pasman-Ugljan bridge, which has spelled disaster for numerous sailing boats, a motorboat provides the perfect chance!

Space and comfort

Broadly speaking, aside from mega yachts or specialist vessels, motorboats provide more space both below and on deck compared to similarly sized sailboats. They also typically feature multiple deck levels. So you can bask in the sunshine on one deck, and find shelter in the shade on another. Furthermore, on a motorboat, you don't have to fret about a precarious jib or the risk of tripping over winches or ropes. The deck tends to be more open and free from sailing gear, allowing for easier movement and relaxation.

If you have crew members who do not tolerate the heeling of a sailboat well, this concern is completely eliminated with motor boats. Unless you're faced with sizeable waves, the boat is likely to maintain stability and you won't need to worry about any significant tilting. This makes a motorboat a more comfortable choice for those sensitive to the motion of the sea.

You wouldn't find such a load on a motorboat

A leisure sailboat simply can't match the speed of a powerboat. While most sailboats average around 7 knots, motorboats can easily reach 15 to 20 knots. If you enjoy the thrill of speed and the feeling of wind in your hair, a powerboat is the perfect choice for you.

Consumption and costs

On the flip side, with the increased speed comes higher fuel costs. While on a sailboat, you might only need to refuel at the end of your trip or 2-3 times a week at most, resulting in a manageable fuel bill. However, if you're sailing for extended periods each day on a motorboat, you'll find yourself refuelling frequently, at a higher cost, and spending a significant amount of time waiting to fill up the diesel tank.

Level of effort and work

Starting a motorboat is straightforward; turn it on and off you go, cruising wherever you fancy. There's no need to fuss over ropes, the jib, sails, lazy bags, lazy jacks, or the whereabouts of the crank. Unlike on a sailboat where there's always something to keep you occupied, a motorboat offers pure relaxation and peace of mind. If you're seeking a laid-back cruising experience, a powerboat is the way to go.

Sailing direction

As long as there are no big waves and the Bora is not blowing against you, you can sail your motorboat comfortably pretty much anywhere you want. This isn't the case with sailboats, where you might have to cruise or alter your destination if the wind is blowing directly against you. While sailboat enthusiasts often say, "the journey is the destination," powerboat users are more about reaching their destination promptly and without fuss.

What is the difference between a motor boat and a sailboat?

Despite their differences, powerboats and sailboats do share some commonalities, with maintenance being the prime one. Regardless of the type of boat you own, upkeep is crucial. This includes taking care of the sails or engine and ensuring regular servicing. Moreover, marina fees apply uniformly to both. The harbour masters charge based on the length of the boat, irrespective of whether it's a sailboat or a powerboat. The only exception might be a catamaran, which typically incurs a higher fee due to its dual-hulled design, making it wider and potentially occupying the space of two conventional berths.

Disadvantages of motor boats

While motor boats offer numerous advantages, it's important to consider their potential drawbacks as well. Let's take off the rose-tinted glasses and delve into some of the downsides associated with powerboats.

Fuel dependency and non-environmental operation

Unlike a sailboat that can harness the wind as a natural and free power source, a motorboat is completely reliant on diesel fuel. Running out of fuel in the middle of your journey can leave you stranded. Furthermore, this dependence on fossil fuels also means that operating a motorboat has a greater environmental impact compared to sailing.

YACHTING.COM TIP: Speaking of ecology, check out our guide — Green sailing: 11 tips for eco-friendly yachting . 

Less stability in wind

Motorboats lack a significant keel, resulting in reduced stability when faced with waves and strong winds. Consequently, it is advisable to opt for motorboat rentals during the summer season, when occurrences of powerful winds and waves are comparatively infrequent.

Calm and the smell of the sea

The sound of the engine never leaves you during your voyage which can get on people's nerves. Likewise, the typical smell of burning diesel can start to bother you after a while.

Who is a motor boat best suited for?

A motor boat is well-suited for individuals seeking relaxation, tranquillity, and minimal effort. With the simple act of starting the engine, you can swiftly set sail without any additional concerns. Plus, a motor boat is highly recommended for those who desire to explore a wide range of places, including beaches and other scenic locations. It is particularly advantageous for covering long distances between islands and the mainland within the typical timeframe of a one or two-week vacation. Motor yachts are also a favourable choice for yachters who enjoy fishing, as they provide a comfortable and convenient means of transportation for navigating to different areas and indulging in fishing activities.

YACHTING.COM TIP: Find out what else you can do while sailing in our article — Top 12 fun activities to do on a sailing holiday .

Fishing is an great addition to a boating holiday.

For nature lovers seeking harmony and a closer connection to the natural environment, a sailboat is more preferable than a motorboat. Sailboats provide a serene atmosphere and allow for a deeper appreciation of nature. Additionally, if the aim is to foster teamwork and engage in shared experiences, a sailboat offers more opportunities as it involves handling ropes and sails.  But if you want to relax with a bunch of friends, there's nothing better than a powerboat.

Motor boat season

Unlike sailing boats that typically operate in Europe from April to November, motor boats have a more limited season. The majority of motor cruising occurs between June and September, with peak activity in June and July. Other times of the year, motor yachts are less commonly seen at sea. This is because before and after this season, conditions tend to be windier and the sea becomes cooler, which is more appealing to racers on sailing yachts rather than those seeking a tranquillity on a motorboat, particularly in destinations like Croatia.

YACHTING.COM TIP: What winds and weather will you encounter in the Mediterranean over summer? Check out our guide — The 7 most common winds you'll find in the Mediterranean . 

Motor boat licence

The licence needed to operate a motor boat depends on two criteria — the engine power and the area where you will be boating (whether sea or inland waters). If you want to cruise on a motor boat with an engine power of  less than 4kW , then you don't need a licence. This applies to houseboats or small boats, for example. You can sail a boat with a 4kW to 20kW  engine on inland waters with a VMP licence, but for the sea you'll need an international skipper's licence just as for a sailing boat and in some countries (such as Croatia), a radio licence. With engine power  above 20kW , for inland sailing and on the sea, you will need a certificate of engine experience for inland sailing in addition to the VMP.

YACHTING.COM TIP: Still hesitating about getting your skipper's licence? Take a look at our 5 reasons to take a skipper's course . Then check out our sailing courses and you'll soon be sailing the seas!

How to choose a motor boat?

Motor boats have a slightly different interior layout than sailboats. The smaller ones often have only one or two cabins and it is automatically assumed that the other couple sleeps in the saloon, often in the bow. Check before you make your final booking that you will have plenty of privacy. Small motor boats are designed for a couple or small family rather than several people who don't know each other.

Route planning

When choosing a boat, take note of how much the boat consumes. You may find that the fuel will cost you the same amount of money as the charter itself in a week's sailing. Plan your itinerary in advance so you know what to expect.

YACHTING.COM TIP: Want to enjoy your cruise to the fullest and without a care in the world? Try hiring a professional skipper or hostess for your yacht. They'll take care of running the boat, cleaning and cooking, leaving you to relax and spend time with your loved ones. Just ask our sales team.

Highly renowned motor boat brands in the charter industry

Here we have picked out the most popular types of motor boats from our search portal.

Probably the most infamous brand of motorboats is Merry Fisher. The Merry Fisher 795 models are among the best sellers and the Merry Fisher 895 is a common sight cruising the coastline of Croatia. Another sought-after model is the Antares 9 OB , which is generously equipped for a comfortable boating holiday, but if you're after something bigger, the Antares 11 Fly is a great choice. The Greenline 33 or its larger sibling, the Greenline 39 , are also fantastic options.

The popular Antares 9 OB model.

Other types of motor boats

Every motor boat is unique, and there can be a wide range of vessels categorized under the name "motor boat." Let's explore some intriguing and lesser-known motor boats that have distinctive features and stand out from the norm.

Small motorboat

Charter services also offer the option to rent small motor boats, which are perfect for day trips to secluded beaches, nearby islands, or bays that are inaccessible by foot. These boats are typically compact and may not have cabins, making them suitable for short excursions. They are particularly recommended for families who have rented an apartment by the sea and wish to explore the surrounding areas by water. In many cases, these small motor boats are equipped with relatively low-powered engines, and in several countries, you may not even require a skipper's license to operate them. We recommend, for example, the Zodiac Madline 2 or the slightly larger Four Winns H210 .

You can also rent a smaller boat.

Few people can buy a superyacht. And although many more people can rent one, it is still quite expensive. A superyacht or megayacht is considered to be a boat longer than 80 feet but you'll have to hire a professional skipper as only a handful of skippers have a licence for a boat of this length. For example, we offer the superyacht Azimut Grande 27 or MY Custom Line 52 m . These can cost up to 100,000 euros to hire for a week, but the price often includes a crew to look after the boat (including the professional skipper).

Superyacht Azimut Grande 27

The main difference from the motor boats we rent at sea is that houseboats sail on freshwater streams and are designed for exploring rivers, canals, lakes, ponds, and dams. Although houseboats generally have less powerful engines, this feature often allows them to be rented without a license in most destinations. It's important to note that these houseboats are far from mundane, offering a unique and enjoyable holiday experience on calm waters. Check out these breathtaking destinations you can explore on a houseboat.

YACHTING.COM TIP: Never been on a houseboat?  Take a look at our our guide —   First time on a houseboat: 25 things you need to know!

This is what one of the most popular houseboats, the Nicols Estivale Sixto Prestige, looks like.

Power catamaran

Recently, motor catamarans or power catamarans have become more and more popular. They combine the advantages of a catamaran (two hulls, stability, space, nets to lie on,...) while offering the speed, carefree and comfort of a motor boat. Never driven a catamaran? Check out our article — First time on a catamaran: what you need to know

Body of a two-hulled power catamaran.

YACHTING.COM TIP: Wondering what are all the types of boat you can charter? You will be surprised how many there are. Check out the article —  Boats for rent: what types of boats do charter companies offer?

How to operate a motor boat?

If you have sailing experience, driving a powerboat will seem like something very simple. You don't have to worry about ropes, sails, vignettes, masts or a flying jib. You simply start the boat and cruise wherever you want. Then it's the same as mooring with a sailboat.

One important aspect to be aware of when operating a motor boat is the  engine trim . Engine trim refers to the adjustment of the angle between the propeller and the bottom of the boat. Ideally, the propeller should be positioned vertically downward. As a motor boat gains speed, the bow of the boat may lift, causing the propeller to partially submerge. In such cases, it is the responsibility of the captain to intervene and adjust the engine trim to ensure that the propeller is aligned vertically and not at any angle other than 90 degrees to the water surface. This adjustment is crucial to prevent the boat from jumping or unnecessarily impacting the water with the bow. By maintaining the correct trim, the boat can navigate efficiently and provide a comfortable sailing experience for all on board.

YACHTING.COM TIP: Do you know how to operate the outboard motor on a dinghy? Read our article — Dinghy and outboard motor: what you need to know .

Where to sail with a motor boat?

We've selected 3 regions where you can enjoy a fantastic time with a motorboat and take advantage of its superior speed.

Vineyards and islands off Hvar

Start your journey from Split and make your way to the enchanting island of Solta or the sun-soaked Brac. For a glimpse of Croatia's renowned beaches, don't miss out on visiting Zlatni Rat. Proceed to the captivating island of Hvar, where we suggest exploring either the lively town of Hvar itself, the more serene town of Stari Grad, or the authentically charming Vrboska. Indulge in an overnight stay at a tranquil cove on the island of Ščedro, where you can delight in snorkeling alongside majestic clams. Depending on your available time and preferences, continue your voyage to the island of Vis and discover the picturesque village of Komiza, where you can experience the novelty of standing on a buoy or by the pier. During the day, take a trip to the island of Bisevo, home to the famed Blue Spila (blue cave).

Ionian Sea (and turtles!)

Rent a boat on the Greek island of Corfu. Upon taking over the boat on Saturday, take a leisurely stroll to the charming capital, Kerkyra, where you'll be enchanted by its delightful streets and atmosphere. Next, set sail south towards the island of Paxos, renowned for its breathtaking bays. During the day, make sure to indulge in a refreshing swim in Lefkada, a destination in the western part that boasts stunning beaches reminiscent of the Caribbean. Consider spending the night in the lively bay of Vasiliki, known for its vibrant nightlife and one of Greece's most famous kebab joints. The following day, continue your journey to Kefalonia and then proceed onwards to Zakynthos, famously known as the "island of turtles." If possible, sail as far south as you can towards Zakynthos, maximizing your exploration of this captivating destination.

Italian temperament

Experience the enchanting Bay of Naples, beginning in Baiae and venturing to Ischia, where you can navigate its waters at your leisure. Along the way, explore the quaint islet of Procida. Consider Ponza as an alternative to the bustling island of Capri. If time permits, visit the renowned Positano. Carry on to the breathtaking town of Amalfi, with its cliffside houses. Above all, indulge in la dolce vita.

Whether it's a motorboat or a sailboat, I'll find you the perfect choice. Give me a call.

Denisa Kliner Nguyenová

Faq motor boats.

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Definition of motorboat noun from the Oxford Advanced American Dictionary

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Basic Electromyography: Analysis of Motor Unit Action Potentials

After assessment of insertional and spontaneous activity, the needle electromyography (EMG) examination moves on to the evaluation of motor unit action potentials (MUAPs). In a process similar to the analysis of spontaneous activity, MUAPs must be assessed for morphology (duration, amplitude, phases), stability, and firing characteristics. The pattern of MUAP abnormalities that emerges from this part of the examination usually will allow a determination of whether a disorder is primarily neuropathic or myopathic and often helps determine the time course (acute vs. chronic) and severity of the lesion. The assessment of MUAPs often is demanding and improves with the experience of the electromyographer over time. The task of evaluating MUAPs is made all the more difficult by the wide variation in what is considered a normal MUAP, depending on the muscle being studied and the age of the patient. Physiology The basic component of the peripheral nervous system is the motor unit, defined as an individual motor neuron, its axon, and associated neuromuscular junctions (NMJs) and muscle fibers. The extracellular needle EMG recording of a motor unit is the MUAP ( Figure 15–1 ). The number of muscle fibers per motor unit varies greatly, from 5 to 10 in laryngeal muscles to a couple of thousand in the soleus. The transverse territory of a motor unit usually ranges from 5 to 10 mm in adults, with many motor unit territories overlapping with one another. Because of this overlap, two muscle fibers from the same motor unit rarely lie adjacent to each other. Transverse motor unit territory increases greatly with age, doubling from birth to adulthood, mostly because of the increase in individual muscle fiber size. FIGURE 15–1 The motor unit. The basic component of the peripheral nervous system is the motor unit, defined as an individual motor neuron, its axon, and associated neuromuscular junctions and muscles fibers. The extracellular needle electromyography recording of a motor unit is the motor unit action potential (MUAP). When a motor neuron depolarizes to threshold, a nerve action potential is generated and propagates down the axon. Under normal circumstances, this results in all muscle fibers of the motor unit being activated and depolarizing more or less simultaneously. Any variability between muscle fiber depolarization times is due to differences in the length of the terminal axons and in NMJ transmission times. The “size principle” governs many of the properties of motor units ( Figure 15–2 ). The size of the motor neuron is directly related to (1) the size of the axon, (2) the thickness of the myelin sheath, (3) the conduction velocity of the axon, (4) the threshold to depolarization, and (5) the metabolic type of muscle fibers that are innervated. The larger motor neurons have larger axons, with the thickest myelin sheath (hence, the fastest conduction velocity), highest threshold to depolarization, and connections to type II, fast twitch muscle fibers. Conversely, the smaller motor neurons have smaller axons, less myelin sheath, slower conduction velocity, lower threshold to depolarization, and, in general, connections to type I, slow twitch muscle fibers. Thus, with voluntary contraction, the smallest motor units with the lower thresholds fire first. As contraction increases, progressively larger motor units begin to fire. The largest type II motor units fire with maximum contraction. During routine needle EMG, most MUAPs analyzed are thus from the smaller motor units that innervate type I muscle fibers. FIGURE 15–2 Size principle and motor unit properties. During the needle EMG examination, each MUAP recorded represents the extracellular compound potential of the muscle fibers of a motor unit, weighted heavily toward the fibers nearest to the needle. A MUAP recorded just outside a muscle membrane is 1/10 to 1/100 the amplitude of the actual transmembrane potential and the amplitude decreases rapidly as the distance between the needle and the membrane increases. The classification of an MUAP as normal, neuropathic, or myopathic rests on no single finding. As is true of spontaneous activity, recorded MUAPs must be assessed for morphology (duration, polyphasia, amplitude), stability, and firing characteristics before any conclusions can be reached. Morphology MUAP properties vary widely both within and between different muscles. Even within a muscle, there is a wide range of normal motor unit morphology, with MUAP size following a bell-shaped distribution curve ( Figure 15–3 ). Due to this normal variability, normal values of MUAP morphology are based on the mean of many different MUAPs. The analysis of MUAP morphology can be performed on either a qualitative or a quantitative basis. To perform quantitative MUAP analysis, one must isolate 20 different MUAPs for each muscle being studied and measure their individual durations, amplitudes, and number of phases. From these values, the mean duration, amplitude, and number of phases are calculated and compared with a set of normal values for that particular muscle and age group. MUAP morphology varies depending on the muscle being studied and the patient’s age. This is particularly true of MUAP duration ( Table 15–1 ). In general, MUAPs in proximal muscles tend to be shorter in duration than those in more distal muscles. MUAP size in adults is larger than in children, primarily because of an increase in the size of muscle fibers during development. In addition, MUAP size is generally larger in older individuals, probably as the result of dropout of motor units from the normal effects of aging, leading to some compensatory “normal” reinnervation. The loss of motor units has been estimated to be approximately 1% per year, beginning in the third decade of life, which then increases rapidly after age 60. FIGURE 15–3 Range of normal motor unit action potential (MUAP) duration and amplitude. Histogram of MUAP duration and amplitude in the biceps brachii of a normal subject. Note that both MUAP duration and amplitude vary markedly in normal muscles, with small and large units in the same muscle. MUAP duration or amplitude should not be classified as abnormal based on one or two MUAPs but requires a mean of many motor units. (Reprinted with permission from Buchthal, F., Guld, C., Rosenfalck, P., 1954. Action potential parameters in normal human muscle and their dependence on physical variables. Acta Physiol Scand 32, 200.) Table 15–1 Mean Motor Unit Action Potential Duration Based on Age and Muscle Group Age of Subjects Arm Muscles Leg Muscles Deltoid Biceps Triceps Thenar ADM Quad, BF Gastroc Tib Ant Per Long EDB Facial 0–4 7.9–10.1 6.4–8.2 7.2–9.3 7.1–9.1 8.3–10.6 7.2–9.2 6.4–8.2 8.0–10.2 6.8–7.4 6.3–8.1 3.7–4.7 5–9 8.0–10.8 6.5–8.8 7.3–9.9 7.2–9.8 8.4–11.4 7.3–9.9 6.5–8.8 8.1–11.0 5.9–7.9 6.4–8.7 3.8–5.1 10–14 8.1–11.2 6.6–9.1 7.5–10.3 7.3–10.1 8.5–11.7 7.4–10.2 6.6–9.1 8.2–11.3 5.9–8.2 6.5–9.0 3.9–5.3 15–19 8.6–12.2 7.0–9.9 7.9–11.2 7.8–11.0 9.0–12.8 7.8–11.1 7.0–9.9 8.7–12.3 6.3–8.9 6.9–9.8 4.1–5.7 20–29 9.5–13.2 7.7–10.7 8.7–12.1 8.5–11.9 9.9–13.8 8.6–12.0 7.7–10.7 9.6–13.3 6.9–9.6 7.6–10.6 4.4–6.2 30–39 11.1–14.9 9.0–12.1 10.2–13.7 10.0–13.4 11.6–15.6 10.1–13.5 9.0–12.1 11.2–15.1 8.1–10.9 8.9–12.0 5.2–7.1 40–49 11.8–15.7 9.6–12.8 10.9–14.5 10.7–14.2 12.4–16.5 10.7–14.3 9.6–12.8 11.9–15.9 8.6–11.5 9.5–12.7 5.6–7.4 50–59 12.8–16.7 10.4–13.6 11.8–15.4 11.5–15.1 13.4–17.5 11.6–15.2 10.4–13.6 12.9–16.9 9.4–12.2 10.3–13.5 6.0–7.9 60–69 13.3–17.3 10.8–14.1 12.2–15.9 12.0–15.7 13.9–18.2 12.1–15.8 10.8–14.1 13.4–17.5 9.7–12.7 10.7–14.0 6.3–8.2 70–79 13.7–17.7 11.1–14.4 12.5–16.3 12.3–16.0 14.3–18.6 12.4–16.1 11.1–14.4 13.8–17.9 10.0–13.0 11.0–14.3 6.5–8.3   ADM, abductor digiti minimi; BF, biceps femoris; EDB, extensor digitorum brevis; Gastroc, gastrocnemius; Per Long, peroneus longus; Quad, quadriceps; Tib Ant, tibialis anterior. Reprinted with permission from Buchthal, F., Rosenfalck, P. Action potential parameters in different human muscles. Acta Psychiatr Neurol Scand, © 1955 Munsgaard International Publishers Ltd, Copenhagen, Denmark. Only by comparing mean MUAP morphology in each muscle studied to normal values for that particular muscle and age group can one determine whether the morphology is truly abnormal. Previously, quantitative MUAP analysis was tedious and time consuming. However, many modern EMG machines now have programs that largely automate the procedure. With experience over time, however, the well-trained electromyographer usually can perform qualitative MUAP assessment with the same precision as can be achieved using quantitative methods. Essentially the same procedure is used. The needle is moved to several locations within the muscle until approximately 20 different MUAPs have been examined, qualitatively analyzed, and compared to the expected normal values for that particular muscle and age group. Duration MUAP duration is the parameter that best reflects the number of muscle fibers within a motor unit ( Figure 15–4 ). Typical MUAP duration is between 5 and 15 ms. Duration is defined as the time from the initial deflection from baseline to the final return of the MUAP to baseline. It depends primarily on the number of muscle fibers within the motor unit and the dispersion of their depolarizations over time. Dispersion in turn depends on the longitudinal and transverse scatter of endplates and on variations in terminal distances and conduction velocities. Duration lengthens as the number of fibers and the territory of a motor unit increase; it varies directly with age (increased age, increased duration) and inversely with temperature (decreased temperature, increased duration) and depends on the individual muscle being studied. Proximal and bulbofacial muscles in general have MUAPs of shorter duration. When performing EMG, it often is more rewarding to listen to the potential than to see it. This is especially true when evaluating MUAP duration, because duration correlates with pitch . Long-duration MUAPs (low frequencies) sound dull and thuddy, whereas short-duration MUAPs (higher frequencies) sound crisp and static-like. As the electromyographer gains experience, the sound of a long-duration versus a short-duration MUAP becomes unmistakable. FIGURE 15–4 Motor unit action potential (MUAP) measurements. Duration is measured as the time from the initial deflection of the MUAP from baseline to its final return to baseline. It is the parameter that best reflects the number of muscle fibers in the motor unit. Amplitude reflects only muscle fibers very close to the needle and is measured peak to peak. Phases (shaded areas) can be determined by counting the number of baseline crossings and adding one. MUAPs are generally triphasic. Serrations (also called turns) are changes in direction of the potential that do not cross the baseline. The major spike is the largest positive-to-negative deflection, usually occurring after the first positive peak. Satellite, or linked, potentials occur after the main potential and usually represent early reinnervation of muscle fibers. Polyphasia, Serrations, and Satellite Potentials Polyphasia is a measure of synchrony, that is, the extent to which the muscle fibers within a motor unit fire more or less at the same time. This is a nonspecific measure and may be abnormal in both myopathic and neuropathic disorders. The number of phases can be easily calculated by counting the number of baseline crossings of the MUAP and adding one ( Figure 15–4 ). Normally, MUAPs have two to four phases. However, increased polyphasia may be seen in up to 5 to 10% of the MUAPs in any muscle and is considered normal. The one exception is the deltoid, where up to 25% polyphasia may be normal. Increased polyphasia beyond 10% in most muscles and 25% in the deltoid is always abnormal. Through the speaker, polyphasic MUAPs are recognized as a high-frequency “clicking” sound. Serrations (also called turns) are defined as changes in the direction of the potential that do not cross the baseline. Increased polyphasia and serrations have similar implications, indicating less synchronous firing of muscle fibers within a motor unit. Often, a serration can be changed into an additional phase with needle movement. Satellite potentials (also known as linked potentials or parasite potentials ) are interesting phenomena seen in early reinnervation. After denervation, muscle fibers often are reinnervated by collateral sprouts from adjacent intact motor units. The newly formed sprout often is small, unmyelinated or thinly myelinated, and therefore very slowly conducting. Because of the slow conduction time and increased distance, reinnervated muscle fibers are seen as time-locked potentials that trail the main MUAP ( Figures 15–5 and 15–6 ). These satellite potentials are extremely unstable (see section on Stability ) and may vary slightly in their firing rate or may block and not fire at all ( Figure 15–7 ). Over time, the sprout matures, and the thickness of the myelin and consequently the conduction velocity increase. The satellite potential then fires more closely to the main potential and ultimately will become an additional phase or serration within the main complex. It is usually necessary to put the main MUAP on a delay line to appreciate a satellite potential and to demonstrate that it is time locked to the main potential. FIGURE 15–5 Collateral sprouting and satellite potentials. A: Normal state. B: Following partial denervation, the injured axon(s) undergoes wallerian degeneration. C: Reinnervation commonly occurs from sprouting by adjacent surviving axons. In early reinnervation, sprouts are small and thinly myelinated and conduct slowly. Because of the slow conduction time and increased distance, these reinnervated fibers initially occur as time-locked potentials (satellite potentials) trailing the main motor unit action potential (MUAP). As sprouts mature and conduct more quickly, the time-locked potentials are eventually incorporated into the main MUAP, resulting in an MUAP with increased amplitude, duration, and number of phases.

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