From knowledge to muscle

Speed skating is one of the most popular sports in the Netherlands during the winter season. When the temperature drops below 0°C, the lakes and canals freeze over and the heartbeat of the Dutch begins to rise. If the winter is severe enough, the famous 11 cities skating race can take place—a 200 km tour along frozen canals, rivers and lakes.3 This was last held in 1997 and it is known that finishing this tour is a strong indicator of longevity.4 Acute muscle injuries in speed skating are rare,5 which is in stark contrast to other popular sports in Holland like football and field hockey. The fact that muscle injuries are common in these sports, a hot topic in sports medicine at the moment, and a number of publications from Dutch Sports Medicine researchers made this the obvious choice for this themed issue.

Preventing sore muscles

In all types of sport, it is desirable to prevent the onset of delayed onset muscle soreness or to improve the rate of recovery. In this edition, we include one systematic review showing the potential effect of compression garments (see page 1340) and another that evaluates the effects of cold water immersion (see page 1388). Have you considered using one of these interventions for your team or player?

Muscling out PRP

An important aim for team physicians is to accelerate recovery and get athletes playing again as quickly as possible. Novel therapies, like the delivery of growth factors through platelet-rich plasma (PRP), are frequently used for this purpose in daily clinical practice. Reurink et al6 recently published their study results in the New England Journal of Medicine, which showed that there is no additional benefit of PRP injections in the management of acute hamstring muscle injuries. This excellent paper describes the first randomised controlled trial in the field of PRP injections for muscle injuries. In his editorial, Dr Bruce Hamilton discusses the contents of this article (see page 1336) and you can also access a podcast on hamstring injuries with Guustaaf Reurink (bjsm.bmj.com/site/podcasts/).

Predicting muscle recovery and reinjury

Sophisticated imaging is often used as a tool to measure recovery and clear an athlete to return to play. However, two papers in this issue (see pages 1358 and 1364) show that MRI abnormalities and isokinetic deficits are still present in athletes who are clinically fully recovered. It is therefore questionable if these tools are useful as parameters of recovery. Dr John Orchard discusses the role of MRI in muscle injuries in his editorial (see page 1337). The role of the initial MRI is also evaluated as a predictor of time to return to play (see page 1370) and as a measure of reinjury risk (see page 1377).

The future? A new classification system of muscle injuries

A better classification system of muscle injuries would be a helpful instrument from a research and clinical perspective. In this issue, a new classification system is described (see page 1347) and hopefully this will lead to better understanding and management of muscle injuries. On a similar note, Finch and Cook7 tackled the challenge of categorising subsequent sports injuries (acute, reinjury or chronic) and propose a new model for discussion, which Shrier and Steele evaluate in their editorial (see page 1338).

I hope that all BJSM readers will find this special Dutch Association of Sports Medicine (VSG) issue interesting and useful for their research, in their clinical practice, as well as in educating athletes and support staff. Because in the end, what you know is only valuable when it impacts your daily practice; “Knowledge is only rumour, until it is in the muscle.”