Should you stretch before a workout? At one-time fitness experts believed that stretching reduced the risk of injury by warming up the muscle, but more recent research shows that static stretches may actually increase the risk of injury by causing the muscle to tighten rather than relax.
When you do a static stretch using muscles that aren’t already warmed up, your muscles sense they’re being overstretched and compensate by contracting. This leaves you with tighter muscles. This reduces the ability of the muscle to generate power and increases the risk of injury. According to one study, static stretching decreases muscle strength by 30%. Because of this risk, many experts no longer recommend doing static stretches before working out but instead suggest starting with a warm-up like jogging in place.
Still, there is a place for stretching as long as you know when to do them and not do them. There are actually several types of stretches, and it’s important to understand the differences between them.
Static Stretches
Static stretches are where you hold a muscle or muscle group in a stretched position for 10 to 30 seconds. An example is stretching your leg out and placing your heel on the floor and holding this position for 30 seconds to stretch your hamstrings. This type of stretch is best at the end of a workout when your muscles are already warm.
Dynamic Stretches
Dynamic stretches involve elongating a muscle in a more fluid way that uses momentum. Rather than holding a stretched position, you keep the muscle constantly moving. Examples of dynamic stretches are torso twists, arms swings, butt kicks, high knees, legs swings, and walking lunges. Movements are dynamic and fluid, and there is no bouncing.
Ballistic Stretching
Ballistic stretching is a type of stretch where you assume a stretched position and bounce in and out of it. An example is bending over to touch your toes and bouncing up and down or getting into a lunge position and bouncing. Ballistic stretching forces muscles to push beyond their normal range of motion, which can increase the risk of injury if done improperly. It’s best to avoid this type of stretching entirely, especially when your muscles are cold.
Proprioceptive Neuromuscular Facilitation
This type of stretching is often referred to as PNF. This is a more advanced stretching technique that requires a partner. An example would be raising your leg up in the air while lying on the floor and having a partner try to hold it up while you push down. Some athletic trainers and physical therapists use this type of stretching to help athletes increase their flexibility and range of motion quickly, but it’s inconvenient to do unless you have someone to assist you.
Which Stretch is Best?
Before a workout when muscles are still cold, it’s best to start with a sport-specific warm-up. Prior to running, warm up by jogging in place for a few minutes. Prior to a strength-training workout, do a few minutes of dynamic stretches such as torso twists and arm and leg swings to increase your core body temperature and range of motion. If you do static stretches, do them at the end of your workout when your muscles are warm. There’s no evidence that static stretches reduce the risk of injury, and they may increase it. If you do static stretches, never stretch beyond the point where it feels comfortable and avoid jerking or bouncing.
References:
Strength and Conditioning Journal, Vol 22 no 5, Pgs 33-38.
MSNBC. “Want a Better Workout? Don’t Stretch”
Science Daily. “Stretching Before a Run Does Not Necessarily Prevent Injury, Study Finds”
Related Articles By Cathe:
Mobility vs. Flexibility: They Aren’t the Same Thing but They’re Both Important
5 Stretching Mistakes You’re Probably Making
Does Stretching Actually Lengthen Muscles?
How Flexibility Changes with Age
Does Resistance Training Reduce Flexibility?
5 Reasons Why It’s Important to Warm Up Before Exercise
