Benefits of Static Stretching in the cool down :

You can do some active static stretching holds then finish of with some relaxing passive stretches. An example of an active stretch would be holding a donkey kick by squeezing glute as hard as you can and then a passive stretch for the same muscle would be a pigeon stretch.

It Should Be A Must In The Cool Down Phase:

1. Increases range of motion which makes you more flexible to combat the natural loss of flexibility that comes with aging (Making us stiff). It helps us maintain muscle elasticity, length and suppleness (as muscles get rigid and hard with excessive tension). Improving extensibility of the Musculotendionous Junction which helps in reducing strain injuries

2. Increases Nutrient exchange and oxygen uptake which can give you more muscle energy and efficiency. Helps get rid of metabolic waste like carbon dioxide, ammonia and uric acid.

3. It can help ease pain from overly tensed muscles by releasing excess tension. reduces overall tension to give us mental and physical relaxation. This can help healing and recovery, a regular stretching routine can prevent excessive muscular tension.

4. Helps with nerve and fascia health, both systems work together to allow movement and regulate tension. Short and tightened muscle do not allow fluid or powerful movement. Realigns fascia and enables smooth gliding by removing adhesions

5. Prevents & treats short Hypertonic muscles, which can weaken (inhibit) opposing muscles and cause a joint dysfunction. Known as altered reciprocal inhibition (which in very extreme cases can lead to disability if not resolved (fibrotic contractures)).

6. Releases tension from the spine and eases pressure from other muscles tugging on the spine. Excessive tension reduces neuromuscular efficiency. Decompresses spine to reduce wear and tear. Prevents adaptive shortening.

7. Helps relax tissues for improved healing. lowers chance of knots (trigger points) formation. Reduces fascia restrictions (tightness)

8. Prevents Muscles from becoming too short (altered resting length), therefore prevents impaired movement patters (compensation). Strong and flexible muscles reduce the chance of injury which increases with weak and inflexible muscles. Muscles activate and co-ordinate better when not tightened up. Reduces the chances of a pulled muscle injury and over-use injuries.

9. Increases blood flow to the muscles which can help with many chemical processes. A tense or tight muscle restricts the blood flow slowing down the chemical processes.  During static stretching, blood flow, capillary region oxygenation, and the velocity of red blood cells to the muscle appear to decrease. Perhaps this is to be expected as the mechanical strain exerted on the muscle from the stretch is likely to cause vascular compression and lengthening. However, immediately after the stretch is released, blood flow appears to significantly increase beyond its previous pre-stretching levels.

10. Helps destress the body and mind, it can be a valuable tool to fight depression along side other exercises. Activates the parasymphatic nervous system which helps relax you and gives you a feel good feeling. 

11. Destresses joints, a chronic stretching program can boost performance and prevent some injuries. Can help prevent muscle imbalances (joint dysfunction) and the improved range of motion will give us better movement and may reduce some injuries. A good strength and flexibility program is best way to reduce injury potential. Makes joints lighter and move easier with more fluid motion. Reduces heavy feeling in joints.

12. Keeps arteries, veins and capillaries healthy. Also helps keep glucose levels, blood pressure and metabolism healthy. Reduces cholesterol and increases muscle energy.

13. Is used alongside strength exercises to treat bad posture. Can also prevent bad posture in the first place. The better your posture the less chance of injury and the better your performance, due to better optimal movement patterns.

14. Aids in getting a good sleep. Relaxes muscles via autogenic inhibition. Elongates muscles by opening them up and eases tension.

15. Used On bedridden people to try and prevent contractures. 

16.  Improves mechanical efficiency and overall functional performance. Because a flexible joint requires less energy to move through a wider range of motion, a flexible body improves overall performance by creating more energy-efficient movements.

17. It can help prevent muscle knots, and help reset proprioceptors, which provide information about joint angle, muscle length and muscle tension. Inhibits and calms down the muscles to bring back to a more relaxed state after activity.

18. Can help make scar tissue from injuries more flexible. Can also help rehab over-use injuries.

1. Safety: Never overstretch a muscle , you should feel no pain if your stretching right.

Stretching For Joint Health (extract from a physio thearpy site)

Without stretching, adaptive muscle shortening accumulates over time, causing muscle imbalances that distort the normal vertical postural alignment (which increases the risks of repetitive stress injury, sports injuries, and falls). As time progresses, joint pain further inhibits use of the full joint range of motion, and next the joint capsule (containing the synovial fluid that nourishes the articular cartilage inside the joint) becomes retracted, increasing mechanical joint compression, finally leading to the premature development and accelerated progression of osteoarthritis.

Unlike muscle stretching that can be performed by the lay person, once the joint capsule becomes restricted, a highly trained medical professional like a Physical Therapist is required, to apply specific techniques and graduated, systematic forces to restore the normal structure and function of the joint capsule.  Left untreated, restricted joint capsules lead to the rapid progression of osteoarthritis and typically results in the eventual need for complete joint replacement.  Many of these surgeries could be avoided or put off (dependent upon the amount of arthritic damage that has already occurred) by receiving PT care including Manual Therapy / Manual Joint Mobilization.

Research study into Stretch & Hearth Health 

The researchers enlisted 39 healthy men and women and split them into two groups.

One group was instructed to do leg stretches five times a week for 12 weeks, and the other group didn’t do any stretching.

Those who stretched saw an improvement to their vascular system. The researchers say this could have implications for diseases that involve changes to blood flow, such as heart attack and stroke.

“In this Italian study, there was a significant improvement in flow-mediated dilation, which can be thought of as the ability of an artery to dilate in response to an increase in blood flow,” said Health Experts.

“This suggests that practitioners should routinely recommend stretching in addition to regular aerobic exercise for patients with vascular disease. The positive changes in arterial function by stretching were not as large as those generally considered to occur with aerobic exercise, but further studies are needed to determine the extent to which passive stretching can complement aerobic exercise.”

If the findings of the study were replicated in people with vascular disease, researchers could determine whether passive stretching may be a suitable treatment for improving vascular health.

“Exercise is one of the most effective ways to ensure healthy arteries, but a lot of the types of exercise that are most studied are cardiovascular focused such as running, walking, biking, swimming. This study is exciting because it shows similar benefits with non-cardio training,” View from a cardiologist.

“If this can be reproduced with vascular disease patients, perhaps it will change exercise programs, cardiac rehab, and other aspects of rehabilitation from vascular disease,” she added.