For many years there has been a debate between exercise physiologists over whether or not athletes should incorporate the use of machines in their flexibility development programmes. In this article I will highlight the pros and cons of both sides of the debate, as well as reveal aspects that appear to have been left out. My aim in publishing this piece on MAP is that it will help you, the general reader, find some clarity in the often confusing and much-debated world of stretching. First I will address the arguments against the inclusion of machines in a stretching programme. Some of the world’s most respected authors (such as Thomas Kurz and Pavel Tsatsouline) state the following: 1. Stretching machines do not develop strength in the stretched position. (Note: it is a fact that the stronger a muscle is, the less activation is required to support it. In other words, the stronger it is at a full range of motion, the more flexible it is.) 2. Any stretches that can be done with the machine can also be done without it, as is the case of Eastern Bloc Olympians who have never used stretching machines. The methods of Kurz and Tsatsouline advocate the use of isometric stretching (performing short, strong tensions in the stretched position) to achieve two aims: 1) to override the stretch reflex and bring about further gains in range of motion, and 2) to develop strength in the stretched position. They also state an athlete will maximise flexibility gains by supplementing isometric stretching with relaxed stretching (assuming a position and waiting for the tension in the target muscles to subside, then moving into a greater range of motion; essentially waiting out the tension and picking up the slack). However, through my own research I have come to several conclusions and I offer the following benefits for the inclusion of machines in a stretching programme: 1. Isometric stretches can be performed in a stretching machine (apply pressure against the contact points), albeit the tensions may not be as strong as done off the machine. However, in my research I found that while tensions performed with the machine were not as strong as tensions performed without the machine, they were still strong and effective enough to bring about further gains in range of motion. 2. Eastern Bloc physical training establishments such as the Uniwersytet Warszawski (University of Warsaw) Physical Education Department advocate the use of partner stretches such as the one highlighted in the image below: The effects of this stretch are achieved without a partner through the use of a stretching machine as seen in the image below: Therefore although the Eastern Bloc athletes are not using a stretching machine, they are still using the same stretching methodology as utilised with a stretching machine. 3. Kurz, Tsatsouline and others state that the key to inducing further gains in range of motion is to relax as much as possible. However, Kurz (who appears to be the strongest opponent against stretching machines) offers the following position as the primary relaxed stretch for achieving side splits: Although the model in the picture is resting her bodyweight on her arms (as instructed in Kurz’s method), a certain amount of weight is still being placed on the adductors. It is a physiological impossibility for a muscle to relax if even the smallest degree of pressure is applied. Therefore the above position is not as effective at relaxed stretching (i.e. waiting out the tension, and picking up the slack) as the following: The weight is placed on the hamstrings and not the adductors; therefore the adductors are totally relaxed and isolated, which are two key ingredients in effective stretching. When they are relaxed they offer the least resistance, and when they are isolated other muscles cannot be recruited into resisting against the stretch. Therefore the maximum stretch possible can be achieved. 4. Performing side splits can place injure the hip and knee joints. Look at the image below of the “toes forward” side split: Notice the awkward angle of the knee joint. As the athlete’s lower legs slide out to the side, his thighs continue downwards. This places excessive pressure on the medial collateral ligament of the knee. If he keeps going the MCL will snap, or worse, the bottom head of his femur could ram through his knee joint and strike the top heads of the tibia and fibula. Also in the “toes forward” side split the athlete must take care to ensure the pelvis is properly rotated. If not, the top head of the femur will jam into the acetabulum (hip socket). Every time this happens cartilage is worn away, which is difficult to regenerate. In the “toes up” side split (as in the photos of the stretching machines above) the pelvis is already sufficiently rotated and so there is sufficient room for the femur to manoeuvre. The methods of Kurz and Tsatsouline fail to mention this aspect (damage to the knee and hip) when selling their products. Conclusion Stretching machines can offer great benefits to an athlete’s flexibility development programme. An athlete can achieve high levels of ROM without one, but it is my opinion that a stretching machine (in conjunction with other methods such as dynamic, isometric and active stretching) will enable an athlete to achieve his or her maximum flexibility potential without damaging the hip and knee joints. As with all types of physical activity every athlete should perform any exercise in moderation and if in doubt, he or she should consult a qualified physician.