Stretching (Pt 2)

In the previous post we discussed the general anatomy of a stretch and touched on some pointers for stretching effectively. In this second part on stretching we’ll discuss several different types of stretches and get into more of the benefits of stretching safely and effectively.

There are two primary types of stretches: static and dynamic. The first we’re all relatively familiar with and the other is most commonly used by athletes before sporting events. The main difference between the two is the use of movement to achieve the stretch.

Static Stretches

Static stretches are done without any movement. A person will typically get into a stretch position for a targeted muscle and hold it for a given amount of time. This is the type we’re all familiar with. The goal is to hold the stretch until the muscle lengthens. Think of a seated hamstring stretch or reaching down to touch your toes. There are several ways in which static stretches can be performed.

1) Static Stretching: Static stretches are done alone without the aid of a person or device. As previously discussed, the stretch is held for a period of time until the targeted muscle is lengthened. This by far the most common form of stretching done by athletes and non-athletes alike. It’s also the safest form of stretching, making it a good choice for beginners and sedentary people.

2) Passive Stretching: During a passive stretch a person or device is used to perform the stretch. Similar to static stretching, an outside force such as a physical therapist or personal trainer is used to further the stretch. This form of stretching is commonly used in physical therapy while a person is recovering from an injury and does not yet have the strength or mobility to perform it themselves. Personal trainers can assist in passive stretches as a way of deepening the stretch and increasing range of motion.

3) Active Stretching: Performed without the use of an aid or outside force, an active stretch uses an opposing muscle or muscle group (antagonist) to stretch the targeted muscle or muscle group (agonist). For example, when you flex your quadriceps (antagonist) you also stretch your hamstrings (agonist). The advantage here is that contracting the antagonist muscle (quadriceps) will create reciprocal inhibition in the agonist muscle (hamstrings), allowing for a greater stretch.

4) PNF Stretching:  Proprioceptive Neuromuscular Facilitation is a more advanced form of stretching that involves both the stretching and contracting of a targeted muscle or muscle group. This type of stretching was initially developed as a form of rehabilitation to help improve muscle strength and range of motion. It uses both GTO and MSO activity to create this effect. It is usually performed with help of a physical therapist or personal trainer. There are several types of PNF stretches (which are beyond the scope of this article) that use both isotonic and isometric contractions.

a) Isotonic Contraction: The word isotonic means ‘of equal tension’. During an isotonic contraction the muscle maintains a constant tension against resistance as it lengthens (eccentric contracting) and shortens (concentric contracting). We perform isotonic contractions every time we go to the gym and lift weights (i.e. bicep curl), do squats, or even while walking or running.

b) Isometric Contraction: The word isometric means ‘of equal measure or length’. Unlike an isotonic contraction, a muscle performing an isometric contraction will not lengthen or shorten but instead maintain the same length against resistance. Common examples include holding the plank position to strengthen your abs or the standing ‘push against the wall’ calf stretch. Isometrics are a safe and popular form of strength training.

Dynamic Stretches

Dynamic stretches involve movements such as swinging, bouncing, kicking and lunging. This form of stretching, although less common than static stretching, is quite helpful in preparing the body for physical activity before sporting events. There are two different types of dynamic stretching.

1) Dynamic Stretching: During a dynamic stretch, a controlled, soft movement, such as the ones described above, is used to increase oxygen and blood flow prior to physical exertion or activity. Dynamic stretches are often used before sporting events because they help to warm up the target muscles without affecting their performance. Studies have shown that static stretches can have a detrimental effect on explosive movements and the strength output of a muscle. There is no forcing involved in a dynamic stretch. Instead, there is a gradual and controlled increase of movement that is gentle and safe. Dynamic stretching has the added of benefit of mimicking the movements used in a specific sport, raising your heart rate, and increasing your core temperature. Some examples include, shoulder circles, arm and leg swings, walking lunges, and high knee marches.

2) Ballistic Stretching: By contrast, this outdated form of stretching uses the same types of movements to force the muscle past its normal range of motion. Since the muscles aren’t given enough time to lengthen and can easily tighten up, the risk of injury is that much higher. As a result, this form of stretching has fallen out of favor amongst athletes and sports enthusiasts.

Benefits of Stretching

1) Improved Range Of Motion: Stretching helps to lengthen our muscles and increase their range of motion. It allows our limbs to operate over greater distances before damage can occur to the muscles and tendons.

2) Increased Power: An increase in muscle length has a direct impact over the distance our muscles can contract. This in turn equates to power. The more power we have available, the greater our endurance and overall stamina.

3) Reduced Post-Exercise Muscle Soreness: Muscle soreness is a result of micro tears that occur in muscle fiber. Lactic acid is a normal byproduct of these micro tears and can accumulate after physical activity. Stretching helps to alleviate next day soreness by increasing circulation to the muscles and removing these waste products.

4) Reduced Muscle Fatigue: After muscles have been contracting for a period of time, they tend to shorten as a result. Tight, short muscles use up more energy in a resting state and cause their opposing muscle group to work harder against this resistance.

Some other benefits may include, an improvement in posture, better coordination, and increase in energy.

General Rules for Stretching

1) Warm up beforehand: A 5-10 minute warm up helps to elevate the heart rate and increase the body’s core temperature. This in turn helps to loosen our muscles, making them more supple and pliable. It also helps prepare the mind and body for physical activity. An increase in heart rate and respiration aids in blood and oxygen delivery to the muscles.

2) Stretch before and after: Stretching beforehand will help to increase our ROM and prevent the likelihood of muscle strain or injury. Stretching afterwards helps to reset muscle fiber length, rid waste products such as lactic acid, and reduce next day soreness.

3) Stretch gently and slowly: Doing so will help bypass the stretch reflex and MSO activation which can create resistance.

4) Stretch to the point of comfortable resistance: Stretching should not be a painful endeavor. If you push beyond what is comfortable, you will engage the stretch reflex and increase your chances of a strain. Holding the stretch until the muscle lengthens, allows you to go further into the stretch.

5) Remember to breathe: Many people unconsciously hold their breathe while stretching. This creates tension in our muscles and prevents us from fully relaxing into the stretch.