Warm-up

Warming Up

thumb|300px|right|pass-throughs are an excellent way of warming up the shoulder joint.A warm-up is the period before any exercise or activity, which consists of movements designed to raise the core body temperature and bring the mind into focus for the activities that follow. There are several types of warm-ups; the warm-up serves a number of purposes: improving blood flow to the heart, increasing the muscle temperature, protect against injury through improved flexibility of muscles , and provides time for pre-competition or pre-training psychological preparation. Warm-ups generally consist of gradual increases in exercise intensity, some stretching, and activity-specific movements; an example of this would be jogging at a low-intensity pace and increasing it to a moderate pace over time (not vigorous; the sole objective of this phase of the warm-up is to circulate the blood and warm the muscles in preparation for more strenuous activity ), followed by stretching, followed by practice catching and throwing a baseball. It is a common misconception that acceptable warmups may consist exclusively of stretching, especially static stretching; the truth is that an effective warm up has a number of very important key components, which work together to minimize the likelihood of injury and prepare the individual for physical activity.

Identifying the elements of an effective and safe warm up, and executing them in the correct order is critical. Stretching is only one part of an effective warm up and should be used in conjunction with the other components, not exclusively.

Elapsed times may be anywhere from five minutes to an hour, depending on the activity; longer warmups are generally only used by high-level athletes before competition, and may consist of several types of warmups of varying intensity.

Elements of an Effective Warmup

There are several key elements of a safe, effective warmup. Elements of an effective warmup include (it is recommended that warmups follow this order) :

• The General Warm Up

General warm ups increase temperature using non-specific body movements. Common practices include 5-10 minutes of light (low intensity) physical activity such as walking, jogging on the spot or on a trampoline, controlled arm circles, jumping jacks, jump rope, low intensity pool laps, etc.

• Static Stretching

Woman performs a static hamstring stretch.

Stretching is best performed after the muscles are warm, so it is recommended that all stretching be done after a general warm-up. Stretching muscles when they are cold may lead to a tear. Static stretching (stretching a muscle and holding it in this position without discomfort for 10-30 seconds) is considered the safest method of stretching. One shouldn't spend so long doing stretches that the muscles cool down and heart rate returns to normal. It is better to save most static stretching for after an exercise session, after your cool-down. Another thing to consider is that there are few sports where achieving static flexibility is advantageous to success in the sport. According to the principle of specificity it would seem to be more advantageous to perform a dynamic warm-up which more resembles the activity of the sport.

Apart from static stretching, other methods of stretching include ballistic, dynamic and PNF (proprioceptive neuromuscular facilitation) stretching.

• The Sport-specific Warm Up

Specific warm ups increase temperature using similar biomechanics that are to be used in subsequent, more strenuous activity. Some of the best ways to perform a specific warm up is to perform the upcoming exercise at a slow pace. Examples include brief sessions of easy catching practice for cricketers or baseball players, high knees or jogging for runners, shadow boxing for boxers, or side-stepping and slow-paced practice hits for tennis players. Sport-specific warm-ups are often designed by a qualified trainer in that sport.

• Dynamic Stretching

Dynamic stretching consists of a series of exaggerated yet controlled motions similar in nature to the activity that follows. It is similar to the sport-specific warmup. It should be noted that while it increases the range of motion of the joints, it does not promote as much flexibility as static stretching or PNF. This is why it is advisable for athletes to perform static stretching or PNF early on in the training plan to build the flexibility firsthand (if it's needed for their particular sport), and utilize dynamic stretching prior to activity or competition. Typical dynamic stretches include hip, knee, arm, and ankle circles, lunges, high knees, etc.

Passive Warm Up

Passive warm ups increase temperature by external means. Such methods include massages, heating pads, steam baths or hot showers. External techniques, however, are less likely to warm deep muscles. Athletes with physical limitations may benefit from passive warm-up.

Benefits

Warm-ups have been shown to improve the effectiveness of training and it is recommended they are done before every training session.

• Direct physical effects:
  1. Elevation of body temperature
  2. Release of adrenaline
     • Increased heart rate
       • Supplies adequate flow of blood to the heart
         • Warm up of two minutes prior to sudden exertion can decrease relative myocardial hypoxia and decrease blood pressure during exercise
         • Warm up may precede strenuous exercise by as much as 10 to 15 minutes and still decreased arrhythmias indicative of inadequate oxygen to the heart
       • Enables greater speed of oxygen travel in the blood
       • Increased production of synovial fluid located between the joints to reduce friction
         • Allows joints to move more efficiently
     • Dilation of capillaries
       • Enables oxygen in the blood to travel at a higher volume
  3. Increase of temperature in the muscles
     • Decreased viscosity of blood
       • Enables oxygen in the blood to travel with greater speed
     • Facilitates enzyme activity
     • Encourages the dissociation of oxygen from haemoglobin and myoglobin
     • Decreased viscosity within the muscle
       • Greater extensibility and elasticity of muscle fibers
         • Increased force and speed of muscle contraction
  4. Increase of muscle metabolism
     • Supply of energy through breakdown of glycogen
  5. Increase in speed of nerve impulse conduction.
     • Increase sensitivity of nerve receptors
  6. Lowering of activation energy rates of metabolic chemical reactions

See Also

• Cool-down
• Pass-Throughs
• PNF