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Warm up – Increased Heart Rate

Getting your heart rate up increases the amount of blood flowing through your circulatory system. As you undoubtedly know, blood carries nutrients and oxygen to cells and removes waste products and so increasing the rate at which it is flowing increases the rate at which these essentials are delivered to the cells that need them as well as increasing the rate at which potentially damaging waste products such as CO2 and lactic acid are removed. If you force muscles to work harder without first providing them with increased levels of the chemicals they require to do so you dramatically increase the likelihood of injuring those muscles. If you keep stressing a muscle without increasing the speed at which it is able to lose the damaging chemicals it produces when stressed you increase the likelihood of injuring those muscles. With this in mind every good warm up should start with aerobic exercise (if it gets you out of breath it is aerobic). By the end of it you should be out of breath and your pulse should be raised. Once you have done this you are ready for stage two of your warm up. Incidentally, we run. Backwards and forwards across the hall, stopping to do simple exercises such as ab crunches followed by more running.

Warm up – Joint Movement

If a joint is able to move it is known as a synovial joint. On a basic level this means that within the joint is a substance known as synovial fluid. Much like blood synovial fluid serves as a means of providing nutrients to, and removing waste products from the cartilage inside the joint capsule. It also acts as a hydraulic shock absorber for the joint. Synovial fluid is not a standard liquid however. It is a Non-Newtonian Thixotropic Liquid. In a nutshell this basically means that at rest it behaves like a solid, but when subject to stresses it becomes more liquid. This means that in order to effectively cushion the joint and deliver the nutrients the cartilage needs the synovial fluid should be as liquid as it is possible to get it. This can be achieved by simply running the appropriate joints through range of motion exercises. You do not need to actively force the joints to their limits, just get them moving. It is important to realize that both heart rate, and synovial fluid viscosity will return to their resting state if not kept up. This means that if you stop exercising for a few minutes you should put yourself through a mini warm up before starting again. I can't promise that you won’t get injured if you follow these simple guidelines, but I can promise that you will drastically reduce the chances of it happening.

Benefits of a Proper Warm Up:
Increased Muscle Temperature - The temperature increases within muscles that are used during a warm-up routine. A warmed muscle both contracts more forcefully and relaxes more quickly. In this way both speed and strength can be enhanced. Also, the probability of overstretching a muscle and causing injury is far less.

Increased Body Temperature - This improves muscle elasticity, also reducing the risk of strains and pulls.

Blood Vessels Dilate - This reduces the resistance to blood flow and lower stress on the heart.

Improve Efficient Cooling - By activating the heat-dissipation mechanisms in the body (efficient sweating) an athlete can cool efficiently and help prevent overheating early in the event or race.

Increased Blood Temperature - The temperature of blood increases as it travels through the muscles. As blood temperature rises, the binding of oxygen to hemoglobin weakens so oxygen is more readily available to working muscles, which may improve endurance.

Improved Range of Motion - The range of motion around a joint is increased.

Hormonal Changes - Your body increases its production of various hormones responsible for regulating energy production. During warm-up this balance of hormones makes more carbohydrates and fatty acids available for energy production.

Mental Preparation - The warm-up is also a good time to mentally prepare for an event by clearing the mind, increasing focus, reviewing skills and strategy. Positive imagery can also relax the athlete and build concentration.

Both the warm-up and cool-down are integral parts of every physical activity, and they in turn should include some of what are called the 6 S’s (Strength, Stamina, Speed, Suppleness, Skill and (p)sychology).

 
Strength - to increase physical power
Stamina - to improve endurance levels
Speed - to increase velocity
Suppleness – to improve flexibility
Skill – to improve over-all competency and ability
(P)sychology – for a positive mental attitude

Warm-up options
1. General warm-up
To begin your warm-up do 5 minutes of light (low intensity) physical activity such as walking, jogging on the spot or on a trampoline, or cycling. Pump your arms or make large but controlled circular movements with your arms to help warm the muscles of your upper body.

2. Sport-specific warm-up
One of the best ways to warm up is to perform the upcoming exercise at a slow pace. This will allow you to simulate at low intensity the movements you are about to perform at higher intensity during your chosen activity. Typical examples include steady jogging, cycling or swimming before progressing to a faster speed. This may then be followed by some sport-specific movements and activities, such as a few minutes of easy catching practice for cricketers or baseball players, going through the motion of bowling a ball for lawn bowlers, shoulder rolls, 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.

3. Stretching
Any stretching is best performed after your muscles are warm, so only stretch after your general warm-up. Stretching muscles when they are cold may lead to a tear. Stretching during a warm-up can include some slow, controlled circling movements at key joints, such as shoulder rolls, but the stretches should not be forced or done at a speed that may stretch the joint, muscles and tendons beyond their normal length.

Another component of stretching during a warm-up is ‘static stretching’ — where a muscle is gently stretched and held in the stretched position for 10-30 seconds. This is generally considered the safest method of stretching.

Perform a light static stretching routine at the end of your warm-up by stretching each of the muscle groups you will be using in your chosen activity. A static stretch should be held at the point where you can feel the stretch but do not experience any discomfort. If you feel discomfort, ease back on the stretch. Remember not to bounce when holding the stretch. Don’t spend so long doing your stretches that your muscles cool down and your heart rate returns to its resting level. It is better to keep most of your static stretching for after your exercise session, that is, as part of your cool-down.

Studies comparing a warm-up that includes static stretching with a warm-up that does not include static stretching have shown that pre-exercise static stretching improves flexibility, but its effect on injury prevention remains unclear.

Apart from static stretching, other methods of stretching include ballistic, dynamic and PNF (proprioceptive neuromuscular facilitation) stretching, each of which is best done under instruction from a qualified fitness instructor or sports coach.