The knee can be at risk for injury because of the relatively long lever arm of the femur and tibia. Both of these bones are about twice as long as a lug wrench, so the torsional force produced by these long lever arms is substantial. Added to that is the body force that’s six to eight times your weight and transferred to the knee during running, cutting and jumping activities. Changing from quadrupeds to bipedal gait also plays a role in our knees as we change directions because the higher degree of force is concentrated on the knees (or a single knee) with movement instead of balanced on all four legs.
The human knee is made of living tissue and requires warm-up periods prior to athletic endeavors. Techniques to steadily increase your heart rate prior to workouts are crucial for preventing knee injuries. Jumping jacks, biking, walking or rowing are great ways to increase your cardiac output and blood flow before strenuous lower half training.
Dynamic stretching is also important as a mechanism to avoid injury and should be a part of your warm up. Research has indicated that static stretching (ex. lying on the ground and stretching in a hurdler’s stretch) will usually lower athletic performance by pre-stretching muscle-tendon units and changing muscle compliance and elasticity. Rare exceptions, such as dance and rhythmic gymnastics, do better with concentrated static stretching. As the knee increases temperature, there is greater flexibility in our movements and, although there are significant individual variances in flexibility, every athlete functions optimally as blood flow increases.
A great way to increase your flexibility is to concentrate on light static stretches after a workout during the cool down phase (end of your workout). Using foam rollers before and after workouts is also a helpful way to increase flexibility. Men can be especially susceptible to tightness in the iliotibial bands, or the thick outer tendons at the hip.