Active Isolated Stretching

Active Isolated Stretching

Active Isolated Stretching (AIS) is a type of Muscle Energy Technique which has proven to be a very effective way to lengthen shortened muscles quickly, safely and with little warm-up time because the stretch itself is actually a warm-up. AIS is a type of Assisted Stretching which necessarily involves two people. It is used in the clinical environment, but can also be taught for use in the gym during your workouts or at sporting events. What follows is an article that I wrote on this topic in my capacity as Health Columnist for Dalhousie Peer magazine.

High-level athletes will try anything to improve their performance, so current stretching and training theory is always changing.  Ballistic stretching, one of the early forms of stretching, was abandoned several decades ago.  Athletes who tried it found that the rapid bouncing into a stretch caused muscle soreness and sometimes even muscle tears.  After ballistic stretching came “static” stretching, the most common form seen today.  With static stretching, one eases into a stretch and then holds that position for 30 to 60 seconds.  Because there are no rapid movements, proponents argued, static stretching shouldn’t produce soreness.  Instead, it should promote flexibility through gradual adaptation to the stretch.

Many athletes had considerable success with static stretching, while others found that these stretches still caused soreness and didn’t resolve their injury problems. A recently published paper in the Research Quarterly for Exercise and Sport raised questions about the benefits of static stretching. Researchers asked one group of college-aged men to perform a series of 17 stretches ballistically while another group performed the same stretches statically. The results showed that static stretching produced more soreness and higher levels of creatine kinase (an enzyme associated with muscle-tissue injury) than ballistic stretching.  The most likely explanation for this is the “stretch reflex”.  The stretch reflex is a hard-wired body program that is activated after a strong rapid movement, or after two seconds in a stretched position, causing the muscle in question to begin a slow contraction.  If you continue stretching while your muscle is trying to contract, you are risking muscle damage.

Active isolated stretching (AIS) combines the best elements of ballistic and static stretching.  In AI stretching, you hold each position for only 1½ to 2 seconds– then you return to the starting position and relax.  After resting for 2 seconds, you ease into the stretch again.  AI stretching differs from static stretching in another important respect: AI stretches are “assisted” in two ways. First, you begin by contracting the opposing muscle group before stretching the target muscle (this neurologically “shuts off” the muscle you are about to stretch).  Second, while continuing the contraction, you use a rope or your own hands to gently enhance the stretch.  Don’t tug, though- the cardinal rule of stretching remains unchanged: Don’t ever force yourself beyond the point of light irritation.  Stretching is never an instant solution to an injury problem, so take your time.  The best results come from consistent, gentle stretching.

The benefits of AIS over previous forms include; quicker gains in muscle lengthening, less muscle damage, reduced muscle spasm, reduced risk of muscle strain and tearing, increased injury recover speed, and increased athletic performance.  One of the major benefits of AIS is that no warm-up time required.  You can actually do AIS with cold muscles, if done cautiously, because this form of stretching is actually a gentle warm-up for your muscles.  Like all other forms of stretching, AIS also improves flexibility, help to prevent body aches and stiffness, rebalances muscle tone, increases circulation, breaks up internal body adhesions (scar tissue), increases range of motion, increases body awareness, and reduces conscious control over muscle tension.
Getting Started- Follow these steps during each stretch:

  • First contract the muscle group opposite to the area you’re stretching
  • Ease into the stretch actively, then passively overstretch (with the aid of a rope, your hands, or a partner) to the point of light irritation
  • Hold for only 2 seconds
  • Return to your starting position and relax for 2 seconds
  • Repeat the stretch 8 to 12 times

For best results, build up to two sets of 8 to 12 repetitions, exhale during the stretch phase, and inhale during the relaxation phase. Ideally you should perform AI stretching before and after exercise. If time is limited, just do AI stretching after exercise, with fewer repetitions.  The stretches are easy to do once learned, but can be a bit tricky to catch on to without some guidance.

To get started you can contact a personal trainer or a massage therapist for personal instruction.  If you prefer to learn by reading, Aaron Mattes is the granddaddy of AIS.  His books and DVD’s on the subject are available at  Another resource is Whartons’ Stretch Book On Active Isolated Stretching, available at Chapters.