Warm up Flashcards
What is the broad purpose of a warm-up?
To prepare the body for more intense work
What physiological changes can be expected from a good warm-up?
• Slowly increase blood flow to the working skeletal and cardiac muscles
• Lessen the risk of an abnormal cardiac rhythm by increasing heart rate (HR) and cardiac output (CO) slowly
• Improve O2 unloading from hemoglobin (Bohr effect)
• Increase the speed of metabolic reactions
• Increase O2 consumption above resting (enhance O2 uptake at the start of exercise)
• Lead to increased nerve conduction velocity and enhanced neural activation above basal levels
• Increase body temperature above basal (pre-exercise) levels
• Decrease joint stiffness/viscosity by elevating the temperature of synovial fluid, making it less viscous
• Contribute to feelings of well-being, mental preparedness, and cognitive function
What are the key elements of an effective warm-up?
To elevate ventilation of O2 and muscle temperature while minimizing fatigue. An effective warm-up should not be fatiguing.
How does a warm-up benefit the body in terms of metabolic and mechanical preparation?
It acts as a staging or priming of the body, providing an opportunity to up regulate ‘incrementally’ from homeostasis before exercise. This prepares the body metabolically and mechanically. It may enhance performance or the ability to complete a bout of exercise.
Does a warm-up likely reduce the risk of injury?
No, the evidence is not there to support that a warm-up will likely reduce the risk of injury. While there are potential benefits like increased range of motion and less joint stiffness, concrete evidence linking warm-ups to reduced injury risk is lacking.
What happens to different body temperatures (skin, internal, muscle) during a warm-up and exercise?
• Internal (core) temperature takes the longest to increase. However, the goal of a warm-up is primarily to increase muscle temperature, not necessarily internal temperature.
• Skin temperature may initially stay the same and then drop during exercise due to the release of sweat for cooling. A slight sweat indicates elevated body temperature.
• Muscle temperature increases within 5 to 10 minutes of moderate exercise by about 3-4 degrees Celsius, which is a key goal of the warm-up.
Explain the Bohr Effect and its significance during exercise.
The Bohr Effect describes how O2 binding affinity to hemoglobin is inversely related to acidity and the concentration of CO2. When acidity and CO2 levels increase, O2 binding affinity decreases, leading to enhanced unloading of oxygen. During exercise, increased skeletal muscle activity results in localized increases in CO2 and decreased pH (higher acidity), which, due to the Bohr Effect, causes greater oxygen release to the active tissues, proportionally to their metabolic activity. Elevated body temperature also contributes to decreased oxygen binding.
How does a warm-up relate to the oxygen deficit?
A warm-up helps to eliminate the O2 deficit. By gradually increasing oxygen consumption to the level required for the main activity, the body is already consuming oxygen at the necessary rate at the start of the event, thus removing the initial period where oxygen demand exceeds supply.
What are the two main types of warm-ups?
Active and passive warm-ups. Most physical activity/exercise programs involve an active warm-up.
Compare and contrast active and passive warm-ups.
• Active warm-ups involve body movement and induce greater metabolic changes than passive warm-ups. They are generally considered to provide better performance because they involve activating the whole body.
• Passive warm-ups involve external methods of raising body temperature like saunas, hot showers, immersion, or heat application. They can have beneficial effects and are often used in rehabilitation settings. Passive warming allows for testing the hypothesis that performance changes from active warm-ups are largely due to temperature-related mechanisms.
What are the two types of active warm-ups?
General and specific warm-ups.
Describe general and specific warm-ups.
• General warm-up: Low intensity and non-specific, involving whole-body activity. It often precedes a specific warm-up. Duration is typically 5-20 minutes at an intensity of 40-60% VO2 max.
• Specific warm-up: Specific to the muscle groups/fibers, energy system, type of exercise, and component of fitness that will be used in the main activity. It represents a second transition in intensity.
What is Post Activation Potentiation (PAP) and its potential role in a warm-up?
PAP is the influence of high-intensity potentiation that can lead to improved work output in most cases. It involves conditioning contractions (CCs) that can increase sprint speed, jump power, and general muscle power. PAP can be viewed as part of a warm-up on a continuum or as part of the main bout. It is likely more beneficial for highly trained strength individuals. The time frame for benefit is short: ~1-3 minutes after low-volume CCs and ~15-25 minutes after high-volume CCs.
What are the general rules for designing a warm-up?
• The warm-up should be related to the intensity of the main bout.
• The warm-up has to be less intense than the main bout.
• Consider increased intensity for fitter individuals.
• Engage large muscle mass / rhythmic movements.
• Any warm-up is probably better than none, but avoid cooling down after the warm-up before the main activity.
• Avoid making the warm-up too intense or not allowing enough recovery time before the main bout. Warm-ups that are too long (e.g., over 20 minutes if not very low intensity) should also be avoided.
What is the current understanding regarding static stretching as part of a general or specific warm-up?
The majority of evidence supports not including prolonged static stretching as part of a general or specific warm-up. It has been shown to have negative effects on jump, power, agility, and speed. This reduction can last between 15 minutes and 2 hours and is associated with a decrease in neural drive/contractile force and altered musculotendinous compliance.
When might light static stretching be acceptable in a warm-up?
Light static stretching with few repetitions is unlikely to have a significant negative effect. Active warm-ups combined with light stretching can be a good combination. Intense static stretching might only be required in athletes with extreme range of motion needs for their sport.
When should static stretching be performed for flexibility improvements?
Static stretching aimed at improving ROM for performance is questionable when done immediately before activities involving concentric power or ballistic movements. For permanent adaptation to become more flexible, static stretches should be done months in advance or after the performance/activity when muscles are still warm and relatively flexible. To see adaptation, static stretching should be done for 3-6 weeks, though benefits can appear earlier.
What are the acute effects of static stretching on range of motion and how long do they last?
Static stretching can improve range of motion (response), but this effect is often short-lived. About 50% of the acute stretch is gone 10 minutes or later. A static stretch needs to be held for 45 to 90 seconds to have benefits lasting longer than 10 minutes.
How does static stretching affect strength and power performance?
Static stretching has been shown to decrease strength performance, especially high-velocity strength, by 8-10%, likely due to increased musculotendinous compliance. It can also decrease vertical jump performance by 3-4% and sprint performance by 1-2%.
How does dynamic stretching compare to static stretching in terms of performance effects and ROM improvement?
Dynamic stretching does not show a decrease in performance (strength or power) and also improves ROM without the power loss. Active warm-ups alone can show similar benefits to dynamic stretching.
Does pre-game stretching prevent injuries?
No, pre-game stretching does not make you less susceptible to overuse injuries or injuries in general. Static stretching is unlikely to decrease the risk of chronic overuse injuries, traumatic injuries, or other common injuries like sprains.
What are the three strongest predictors of injury risk?
- Age: Risk of muscle strain/tensile injuries increases with age.
- Repeat injuries: A history of injury to a particular muscle-tendon system increases the risk of re-injury.
- Low muscle strength: Insufficient muscle strength is correlated with a higher risk of injury.
What is a cool-down?
A cool-down involves a gradual decrease in the intensity of exercise over a 5-10 (or up to 20) minute period. It can be general, specific, or a combination.
What are the potential benefits of a cool-down?
Benefits may include:
• Reducing the risk of cardiac complications (related to the nervous system), independent of venous pooling, especially in low-fit individuals.
• Preventing venous pooling by allowing arteries to reset to a smaller circumference and maintaining preload to reduce fainting and dizziness.
• Enhanced heat dissipation and feelings of improved recovery.
• Providing an opportunity for stretching while muscles are still warm and relatively flexible.
When is the recommended time to perform static stretching if the goal is to improve range of motion?
Static stretching for flexibility adaptation is best performed after the performance or on a different day than activities requiring power or ballistic movements. This allows for a focus on adaptation rather than just an acute response.
What is a psychobiological measure of training intensity?
A psychobiological measure relates to emotional or psychological factors related to physiology and can be used to assess training intensity.
What is Rating of Perceived Exertion (RPE) and what are its strengths and limitations?
RPE is a valid, reliable, and commonly used psychobiological measure of training intensity. It integrates physiological responses from the muscle, cardiovascular, and respiratory systems into a single global measure. A strength is its ability to incorporate various factors influencing perceived strain. However, it is not a precise method of programming exercise.
Why is it important to consider both relative and absolute measures when prescribing exercise intensity?
Using both relative (e.g., % of 1RM, % of VO2 max) and absolute (e.g., specific weight lifted, running speed) measures provides a more complete understanding of the training load for an individual. A relative measure alone doesn’t indicate the actual workload, which can vary significantly based on individual characteristics (e.g., body mass, strength levels). Providing the absolute value alongside the relative measure offers a clearer picture of the exercise demand.
Is programming exercise solely based on RPE recommended?
No. While RPE is a valuable tool for understanding an individual’s perception of intensity, it is not a precise method for programming exercise. Prescribing specific workloads based on absolute and relative measures is generally more effective for guiding training.
