What is the acute:chronic workload ratio?

Injury is always a problem for athletes in sport and every athlete and team will always be looking at strategies to prevent injuries. There are basically two types of injury that can occur in sport. One is the accident which is much harder to prevent and relies on strategies like rule changes to protect players and the use of protective equipment. The other type of injury is the one related to the training workloads and is often and overuse type of injury. To prevent these types of injuries, then there has to be a careful management of just how much work or training that the athlete does. It is important that training loads are increased slowly and gradually so that the athlete body has time to adapt to the loads that are applied. If there is too much load, then an injury is more likely to occur.

There have been developed a range of monitoring tools which are used to keep a check on the athlete's training to make sure they have adequate rests and breaks to ensure that the body can adapt to those loads. A particular problem is when the athlete has a spike or sudden increase in the training load in comparison to the background training load. A ratio, called the acute:chronic workload ratio has been developed with the acute workload being what the athlete has done in the last week and the chronic workload being what they have done in the last month. If there is a spike in that ratio, then they are considered to be at risk for injury. While this does seem fairly straightforward, there is actually substantial controversy around the evidence that support this model. A recent episode of PodChatLive discussed the issues with Franco Impellizzeri on these problems with the model and how it could be worked forward into the future.