There are several factors that must be considered when performing all stretches. To get the absolute best out of any stretching session, follow these 8 principles and improve the quality of the stretches you provide your clients.

1. Optimal Range of Movement

Know the normal range of movement about each joint and for each muscle group. If you know what is ideal for each joint and what range of movement is required for the person's sport or activity then you are more able to work towards those functional or optimal ranges. Most injuries occur when an attempt is made to make a joint more flexible than it is capable of or required to be. Remember as flexibility improves so must strength through the increased range to maintain joint stability.

2. Postural Positions

Poor posture will cause joint stiffness or laxity. Getting the body into its ideal position will allow for better patterns and more ideal angles of stretch. Maintain good posture through each stretch and look for regional changes which may indicate problems in one part of the pattern you are attempting to stretch. Alignment of the body during the stretching process helps maintain stability through contraction of stabilisers and relaxation of antagonists.

3. Appreciate Good Biomechanics

The movement pattern used to stretch a joint needs to be based on sound biomechanical principles. Trying to twist the joint into a weird position may achieve a stretch but it may not be related to the pattern of movement of the muscles in question or the joint actions. Good biomechanics will ensure the muscles are stretched in the position that they will generally be working through and in the ideal range of movement. Learn how each joint moves and the actions required to achieve a stretch in the associated joints muscles. Study the insertions and lines of pull so you can provide the perfect stretch with better knowledge to support your methods.

4. Leverage

This is the secret to good partner stretching. Use your body weight in such a way that it takes little effort from you but gives maximum effect to your partner. Poor leverage will often mean you’re the one having a workout and you'll fatigue and be less effective. Having leverage during a stretch means having sufficient control over how intense the stretch becomes, and how fast that intensity is achieved. If you have good leverage, not only are you better able to achieve the desired intensity of the stretch, but you do not need to apply as much force via your limbs in order to effectively increase the intensity of the stretch. This gives you greater control. The best stretches provide the greatest mechanical advantage over the stretched muscle. By using good
leverage, it becomes easier to overcome the resistance of inflexible muscles with lighter efforts. Many stretching exercises can be made easier and more effective simply by adjusting them to provide the stretcher greater leverage.

5. Isolations

Ideally, a particular stretch should work only the muscles you are trying to stretch. Isolating the muscles worked by a given stretch means that you do not have to worry about having to overcome the resistance offered by more than one group of muscles. In general, isolating muscles is better for corrective or remedial stretching and stretching chains or muscular patterns is better for gross movements. By isolating the muscle you are stretching, you experience resistance from fewer muscle groups, which gives you greater control over the stretch and allows you to more easily change its intensity.

6. Risk and Pain

Although a stretch may be very effective in terms of providing the athlete with ample leverage and isolation, the potential risk of injury from performing the stretch must be taken into consideration. Even an exercise offering great leverage and great isolation may still be a poor choice to perform. Some exercises can simply cause too much stress to the joints. They may involve rotations that strain tendons or ligaments, or put pressure on the disks of the back, or contain some other twist or turn that may cause injury to seemingly unrelated parts of the body. If you are experiencing pain or discomfort before, during, or after stretching then you need to try to identify the cause. Severe pain particularly in the joints, ligaments, or tendons usually indicates a serious stress of some sort, and you may need to discontinue stretching and/or exercising until you have identified the problem.

7. Duration, Counting, and Repetition

One thing many people seem to disagree about is how long to hold a passive stretch in its position. Various sources seem to suggest that they should be held for as little as 10 seconds to as long as a full minute (or even several minutes). The truth is that no one really seems to know for sure. Many researchers recommend 30-60 seconds. For the hamstrings, research suggests that 15 seconds may be sufficient, but it is not yet known whether 15 seconds is sufficient for any other muscle group. A good common ground seems to be about 30 seconds. Children, and people whose bones are still growing, do not need to hold a passive stretch this long. Holding the stretch for about 7-10 seconds should be sufficient for this younger group of people. A number of people like to count while they stretch. While counting during a stretch is not, by itself, particularly important what is important is the setting of a definite goal for each stretching exercise performed. Counting during a stretch helps many people achieve this goal. Many sources also suggest that passive stretches should be performed in sets of 2-5 repetitions with a 15-30 second rest in between each stretch.

8. Breathing During Stretching

Proper breathing control is important for a successful stretch. Proper breathing helps to relax the body, increases blood flow throughout the body, and helps to mechanically remove lactic acid and other by-products of exercise. You should be taking slow, relaxed breaths when you stretch, trying to exhale as the muscle is stretching. Some even recommend increasing the intensity of the stretch only while exhaling, holding the stretch in its current position at all other times.

The proper way to breathe is to inhale slowly through the nose, expanding the abdomen, hold the breath a moment, then exhale slowly through the nose or mouth. Inhaling through the nose has several purposes including cleaning the air and insuring proper temperature and humidity for oxygen transfer into the lungs as well as a neural reflex which relaxes the body and slows down the heart rate. The breath should be natural and the diaphragm and abdomen should remain soft.

The exhalation should be controlled in a similar manner. As you breathe in, the diaphragm presses downward on the internal organs and their associated blood vessels, squeezing the blood out of them. As you exhale, the abdomen, its organs and muscles, and their blood vessels flood with new blood. This rhythmic contraction and expansion of the abdominal blood vessels is partially responsible for the circulation of blood in the body.