Cross training originates from the introduction of the triathlon in the 1980s whereby many single-sport athletes noted that they performed remarkably well in their previous specialty events despite reduced specific training to allow for multi-event training (Foster et al, 1995).
Cross training works by maintaining the training stress that is already present or enhancing it. This stimulus helps maintain training adaptations that have occurred as a result of training specificity for running. Since cross training involves non specific modalities general peripheral and central adaptations are preserved.
Training adaptations can be separated into peripheral and central categories. The periphery is the cardio respiratory exchange between blood and muscles; accounting for adaptations such as lower blood lactate accumulation, increase in aerobic capacity, enzyme efficiency, mitochondrial density and angiogenesis. Central cardiovascular adaptations include decreased heart rate, increased red blood cell count, increased blood plasma which reduces blood viscosity and increased cardiac output (stroke volume).
"You couldn't always avoid injuries so sometimes you needed to cross train I could tell you stories about the swimming pool. Gary Taylor hurt his knee in his apartment fooling around during cross country season, so we had him in the pool twice per day he would do intervals in the pool. He was back 3 weeks before he had his first indoor meet he said do you think I should run? I'm feeling great I'd say let's do two sessions of 200s, he did and lined up for the first indoor meet and ran 3:58 for the mile and that was a personal-best. He had done nothing but swimming cardiovascular wise. Different guys would go into the pool Daniel Lincoln, Alistair Craig, Joe Falcon, Frank O'Mara. We would go in and do 40 times 30 seconds with 30 seconds recovery and 40 x 1 minute or 20 x 2 minutes. I never had a guy in better shape cardiovascular wise then coming out of a pool. The only thing you are missing is the surface contact but you can solve that but just 2 or 3 weeks of jogging.”
Quote from John MacDonnell in his book. He is the winningest coach in NCAA history. 54 individual champions, 24 Olympians. His Arkansas Razorbacks were dominant!
Conclusion: Why Cross Train?
Hopefully by now I have demonstrated how effective cross training can be when you are injured. This article is coming from a mostly physiological perspective. The psychological benefits are limitless. Not only will your athletes maintain a positive self efficacy, they will keep busy and put their energies into something productive. Be sure to monitor training stress and follow sound principles and use caution when they return to running.
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