Across the Western world, attitudes to cannabis products are changing. Once, weed was prohibited as a controlled substance that would earn you a fine and potentially a criminal record. Today, lighting a joint is starting to be seen as no more shocking than pouring yourself a glass of wine at the end of a hard day. But its role in the world of pro and amateur sport is still far from clear.

Drug testing is a necessary and accepted part of professional sport. Since time immemorial, we've heard of athletes testing positive for weed, and those in the know will tell you its use is widespread. Now we are in a society that allows us to buy cannabis products online or in shops as easily as we can purchase alcohol or tobacco products. Clearly, the time has come to understand what, if any, effect it really has on athletic performance.

Physical benefits
People hear the word cannabis and immediately think of stoners in a state of advanced mental relaxation. However, one of the most exciting outputs of recent cannabis research concerns physical benefits. Studies have found compelling indications that CBD helps to reduce inflammation. Yoga teacher Adam Brous has worked with a number of athletes who have used cannabis to help relieve pain and inflammation associated with muscular injury and surgical recovery.

Another area in which cannabis has delivered positive results is in treatment of muscle spasms and cramps. The potential benefit here for athletes who put so much strain on the knees is evident.

Mental benefits
Marijuana is burdened by incredible volumes of misinformation. The idea that it somehow damages brain function has been largely dismissed by science as an urban myth. In fact, the evidence suggests that the opposite is more likely to be true, and a 2017 study published in Nature Medicine found that small regular doses improved cognitive function in old mice.

It stacks up with the anecdotal evidence. One unnamed pro athlete says cannabis is of huge benefit to his mental focus, helping to reduce anxiety and keep him "in the zone".

What about the risks?
The most common way to consume cannabis is by smoking it. This can lead to lung damage over time, although the evidence suggests it is nowhere near as harmful as regular cigarettes. Nevertheless, lung health is vital for athletes, so they need to think hard about the potential pitfalls of smoking anything at all.

Another concern is that cannabis can impair motor skills, as anyone who has found themselves in a state of "sofa lock" can verify. Clearly, the way cannabis is used and the timing are both important factors. Jamie Feaster is a former athlete who used CBD as an aid to treat tendon damage and who now works in the marijuana sector. He summed up the quandary perfectly when he said: "Marijuana can be a great supplement for recovery after workouts, but I don't recommend using high levels of it when pole-vaulting!"

Research is still ongoing in many areas. However, sport needs to be part of the discussion, as one thing that's clear is that legalised cannabis is here to stay.