By Ebru Efe
The upcoming return to sport brings an exciting but challenging period for many athletes and coaches, involving an attempt to build towards previous training loads and prepare for the return to competition. Many professionals have identified the high risk this brings for particular injuries, including soft tissue injuries such as hamstring and calf strains.
Hamstring strain injuries are a common burden amongst football codes, with mechanisms of injury including speed running, kicking and bending forward to collect the ball. High speed running (HSR), considered to be running at 80-95% of your maximal speed, is identified as the most common mechanism of injury to the hamstring complex, usually involving the biceps femoris muscle.
During HSR, the hamstring complex demonstrates peak levels of force during terminal swing, in decelerating the rapidly flexing hip while extending the knee in preparation for foot strike. This negative (eccentric) work demanded from the hamstrings increases proportional to running speed, and rises exponentially between 80 and 100% of maximal speed.
The volume of HSR completed in training and competition, used as a measure of external training load, is commonly measured by elite athletes and squads through the use of GPS technology. In elite AFL players, the risk of hamstring strain injury appears greatest in those demonstrating a rapid increase in their HSR over the previous 7-14 days. Pending the amount of running completed in isolation, many athletes are likely to expose themselves to this spike in running load in the coming weeks.
While strength training is important, it is difficult to replicate the rapid rate and high force imposed on the hamstring complex during sprinting. Therefore, the best way to protect hamstrings from a running-related injury is to gradually expose them to HSR in training, building this resilience to sprinting over time. Athletes with a high chronic exposure to HSR are better able to tolerate greater sprinting distances in competition, and also demonstrate lower risk of soft tissue injuries compared with those who have either a low level of HSR load or who rapidly increase their HSR over a short period of time.
As an athlete, consider speaking to your coach or physiotherapist to design a safe and appropriate training plan. Remembering to start slow and be patient will help in a successful - and injury free - return to sport.