Either sentence is acceptable. The difference is a question of where the inherent nature is being ascribed. Though it's a very minor emphasis.
The first sentence is emphasizing the inherent nature of the sport. It says "inherent in ... sport" meaning the sport is the source of the inherent nature.
The second is emphasizing the inherent nature to the risk. It says "inherent risks" meaning the inherent nature is part of the risk.
You could, perhaps, try to emphasize the inherent nature as being part of the relationships between the sport and the risk. You could write something like the following. "The presence of risk in sport is inherent." This emphasizes the relationship, presence, as having the inherent nature.
In this case it is a matter of preference. Unless you are specifically trying to make the very minor distinction. For example, you might be approaching it from the point of view of there being a resistant small set of risks that are difficult to remove or reduce. Or you might be approaching it from the view that we should be trying to reduce things to that resistant core, and keeping that core as small as reasonably achievable.