Among sports men and women the term leg strength is broadly understood as someone’s ability to run fast; jump high; kick a ball powerfully or lift a lot of weight in the gym. This type of strength may be useful for performance but what is also important is minimising injury risk and maximising an athlete’s longevity in competition.
With the ever-increasing popularity of weight training it is important that athletes understand how to get the most out of their strength and conditioning sessions and use them not only improve power and strength but also to reduce injury risk.
One of the most neglected aspects of weight training is eccentric strength. An eccentric muscle contraction is when a muscle is holding a load or weight while it is lengthening such as descending to the bottom of a squat. This often-forgotten type of strength is prevalent in most sports as it is crucial for decelerating and changing direction when running and landing in a stable position after jumping.
Taking running as an example, strong links have been made to poor eccentric strength and increased risk of hamstring injuries in rugby players (Bourne et al. 2015). Weak eccentric hamstring strength leads to muscular imbalances between the quadriceps and hamstrings, this is also particularly common in footballers (Ardern et al. 2015). This imbalance causes instability of the knee and increases the risk of hamstring injury, particularly when changing direction or stopping sharply. To prevent this, more emphasis should be placed on eccentric strength and stability during strength and conditioning sessions. This will help enable athletes to have a prolonged and injury free sporting career.