Runner's Web
Runner's and Triathlete's Web News
Send To A friend Know someone else who's interested in running and triathlon?
Send this Runner's Web Story's URL to a friend.
Visit the FrontPage for the latest news.   |     View in Runner's Web Frame

Posted: October 8, 2004

Multisport: Specificity of Training

From Fitness & Health-5th Edition by Brian Sharkey

Fitness and Health-5th Edition

An activity such as jogging recruits muscle fibers uniquely suited to the task. Slow fibers are recruited for slow jogging. The metabolic pathways and energy sources are also suited to the task. Daily jogging recruits the same fibers and pathways over and over, leading to the adaptive response known as the training effect.

The outcomes of training are directly related to the activity employed as a training stimulus. We’ve shown that training has effects on muscle fibers as well as on the supply and support systems, such as the respiratory and cardiovascular systems. In general, the effects of training on muscle fibers are very specific, meaning that they are unlikely to transfer to activities unlike the training. So most of the benefits of run training will not transfer to swimming or cycling. On the other hand, the effects on the respiratory or cardiovascular systems are more general, so they may transfer to other activities (Sharkey and Greatzer 1993).

Training leads to changes in aerobic enzyme systems in muscle fibers, so it is easy to see why those changes are specific. In the early stages of training, the muscles’ inability to use oxygen limits performance. Later on, as the fibers adapt and can utilize more oxygen, the burden shifts to the cardiovascular system, including the heart, blood, and blood vessels. Then the cardiovascular system becomes the factor that limits performance (Boileau, McKeown, and Riner 1984).

Training gains don’t automatically transfer from one activity to another. Training effects can be classified as peripheral (in the muscle) and central (heart, blood, lungs, hormones). Central effects may transfer to other activities, but peripheral changes are unlikely to transfer. However, central changes in blood volume and redistribution may aid performance in another endurance activity. But keep in mind that one-leg training studies show that some part of the heart rate (and stroke volume) change is due to conditions within the muscle fibers, conditions that are relayed to the cardiac control center (Saltin 1977). These changes are specific and will not transfer from one activity to another.

It makes sense to concentrate training on the movements, muscle fibers, metabolic pathways, and supply and support systems that you intend to use in the activity or sport. This does not imply that athletes should ignore other exercises and muscle groups. Additional training is necessary to avoid injury, to avoid boredom, to achieve muscle balance, and to provide backup for prime movers when they become fatigued. In spite of the widespread affection for the term cardiovascular fitness, the evidence suggests that the concept is overrated. Muscle is the target of training.

Finally, if exercise and training are specific, it stands to reason that testing must be specific if it is to reflect the adaptations to training. This means you should not use a bicycle to test a runner, and vice versa. Training is so specific that hill runners are best tested on an uphill treadmill test. How do we test the effects of training on dancers? We don’t. When studies compare runners and dancers on a treadmill test, the runners exhibit higher V.O2max scores. If that is true, why do runners poop out in aerobic dance, cycling, or swimming? Because the effects of training are specific. At present there is no widely accepted way to accurately assess the effects of aerobic, ballet, modern, or other dance forms.

Posted with permission from Human Kinetics Publishers, Inc.

Check out our FrontPage for all the latest running and triathlon news.

Top of News
Runner's Web FrontPage