Is cross-training beneficial? Yes, if you are a recreational athlete. If you are a professional, it will only help you when the other sport is resistance training.
What Is Cross-Training?
The theory behind cross-training is that you have a primary endurance activity you want to get better at and have a certain weakness when performing it. This supposedly can only be addressed if you pick up another activity where you don’t exhibit that weakness.
For example, you are a long-distance runner and if you want to get better at running, you are told you should pick up cycling. The cycling is said to alleviate your running weakness and your running will be better.
Equal At Best
There exists a lot of anecdotal evidence for the the existence of this positive effect and very many coaches still advise athletes to do cross-training. But the scientific results are far more mixed, especially where it concerns professional athletes.
Already in 1994, Dr. Hirofumi Tanaka from the University of Austin, Texas did a meta-analysis of studies looking at the supposed beneficial effect and found that when it comes to performance in endurance activities, cross-training’s effects at best don’t exceed those of sport-specific training.
Interestingly, things look different when the primary (endurance) sport is combined with resistance training: Dr. Tanaka also did an analysis of studies that compared performance in running, biking and swimming when athletes coupled it with weightlifting. Running and biking both benefitted, while swimming did not, the reason probably being that swimmers would need to perform resistance acitivities in water, mimicking their general movements there.
The reason why weightlifting would improve performance in the other two is still not known. Weightlifting probably trains supporting muscle fibers in the legs and that allows runners or cyclists to use them as backups when the main muscles get tired.
Overall Fitness Vs. Performance
To put it simply: If you are a professional athlete, put the focus of your training on your main sport, add some resistance training to your weekly regime and gauge your mileage.
If you aren’t into competitive sports, you are well-advised to follow the recommendations from the American Orthopedic Society for Sports Medicine and the American College of Sports Medicine: do cross-training. It will offer you the best overall fitness possible, while avoiding boredom and getting injuries from doing specific movements for too long and too often.
Picture courtesy of Mike Baird.