How to do PNF stretching
During PNF stretching, a (trained) partner takes you to the end of your natural range of motion at a joint. At that point, you’ll contract your muscles and press against your partner’s hold – that’s an active static stretch – for a predetermined period of time, usually at least five seconds. You then release the contraction.
Because you’ve “tired out” the muscle fibres that engage in the natural stretch reflex, your muscles can be temporarily pushed beyond your initial range of motion to deepen the stretch. Your partner will stretch you again, this time in a deeper stretch. You’ll relax into the stretch this time – that’s a passive static stretch – usually for at least 10 to 30 seconds.
Dynamic stretching is one of the most widely accepted and preferred forms of stretching, especially when included as part of a warm-up to a workout routine. Dynamic stretching involves moving a joint through a full range of motion for a minute or two.
You’ll touch the end of your range of motion but won’t push past the point of comfort. During a dynamic stretch, the muscles surrounding the joint are engaged, increasing blood flow to the area while helping prepare the muscles and joints for more vigorous exercise.
“Stretches should mimic the activity or sport you’re about to perform,” says Michelle Botsford, a physical therapist and strength and conditioning coach. “For example, prior to pitching, a baseball player would want to move through large-amplitude shoulder movements, like arm circles. I typically prescribe four to five stretches to be performed for one to two minutes each.”
It’s an appropriate form of stretching for people of all ages and fitness levels because it’s easily modified to an individual’s personal range of motion limitations.
It’s particularly helpful for athletes, who often have to achieve a larger range of motion while under more significant joint and soft tissue stress. “This makes it important for those structures to be primed for movement,” Botsford says.
Another performance-related benefit: this form of stretching isn’t associated with power or strength deficits that can occur following static stretching. Simply put, if you do static stretching before a competition, it may negatively affect your performance. That won’t happen if you warm up with dynamic stretching.
Fitness and health professionals aren’t so keen on ballistic stretching. Not only does it appear to be less effective than other forms of stretching, but it also may lead to more injuries.
Still curious? Ballistic stretching uses the body’s momentum to bounce into a deeper stretch. For instance, if you can’t touch your toes, you might bend forward and then bounce your torso up and down, trying to force your hands closer to your toes.
The trouble with this is you’re neither relaxing into a stretch nor warming up your surrounding muscle groups to allow for a gradual increase in range of motion. At the same time, you’re moving your body with force in an uncontrolled fashion, which could lead you to push past your stretch reflex in a way that results in a muscle pull or other injury.
Some coaches do continue to use ballistic stretching in controlled settings and with athletes whose sports demand more force and power. But for the general public, it’s best avoided.