Physiologic response of nordic ski racers to three modes of sport specific exercise.

This study compared the response of cross-country skiers to 3 modes of sport-specific exercise. Eight racers completed 2 treadmill tests: ski-walking, and ski-walking with arm resistance provided by a pulley system, as well as a simulated skiing test. Although the average time to exhaustion was significantly less for the skimill test than for the other tests, there were no differences in the maximal responses to exercise. Heart rate, blood lactate, oxygen uptake, minute ventilation and breathing frequency were all significantly greater during the submaximal stages of the skimill test than during the 2 treadmill tests. Anaerobic threshold did not differ between the 2 treadmill tests; however, the addition of arm work significantly delayed its occurrence. Arm pulleys may not increase the specificity of, or add additional work to, a ski-walking test, but rather decrease the demand placed on the athlete by supporting body weight as elevation is increased.