It's hard to imagine that Henry, Beckham, Gerrard and the rest could get much fitter. Footballers, it is said, are such highly-trained, finely-tuned perfectly balanced physical machines that there's little technology left to enhance their performance. But at Stretch Hong Kong, we beg to differ. Active Isolated Stretching (AIS) could help any footballer prevent injury and improve their game.

If you stretch statically, holding each stretch and overloading it with weight before every game, you'll put untold strain on your muscles and starve them of much needed oxygen.

After just five seconds of holding a stretch the tissue becomes locked, which stops blood and essential nutrients reaching the muscle cells, so it becomes less efficient and gets tired faster. AIS on the other hand, gently stretches muscles using a pumping action, forces purifying oxygen into muscle tissue and flushes out damaging toxins such as lactic acid.

Most injuries in football occur at the very end of your range of motion. So if you kick a ball at full knee extension your hamstring will be fully extended. If you have to stretch through your muscle's natural barrier - the point at which your muscle starts to resist movement - and your muscle isn't properly warmed up, your in-built stretch reflex could engage causing a jerk or contraction just when the tissues are at their most extended. The result? A torn muscle that could take up to six weeks to fully recover.

So instead of getting injured, try this AIS stretch for your hamstring.

1. Lye down on a yoga mat or mattress.
2. Isolate your hamstring muscle by rotating and positioning the hip joint so that the leg is straight and the kness turned inwards to isolate the inner fibers of the hamstrings.
3. Contract the opposing muscle group - in this case the quadriceps(thigh) and relax your hamstring muscle. This will switch off your hamstring muscle and make it easier to stretch
4. Hold the stretch at its maximum point for just two seconds, to reduce the chances of activating your stretch reflex, which will cause your muscle to switch off.
5. The stretch shouldn't be painful but just lightly irritating.
6. Repeat the stretch at least 10 times in a row. This will increase blood flow to your muscle to provide nutrients and oxygen.

Quads are the most used and abused of all the major muscle groups, but keeping them flexible could help to prevent knee injuries. To keep yours supple try this stretch:

1. Draw your heel up to your bottom and grasp your ankle.
2. Gently extend you hip by pushing your hips backwards until you feel a light irritation in your thigh.
3. Hold the stretch for two seconds then release and return to the start position.
4. Repeat at least 10 times in quick succession.

Your muscles help to absorb pressure on your body and support your joints, so keeping them balanced and healthy is crucial if you want to avoid injury and stay at the top of your game.

>> learn more about Active Isolated Stretching

>> learn how to stretch for other sports