Well-trained runners (N = 20) were age and ability matched and assigned to either a cross-training or run-only group. Ss
maintained normal running distance and intensity for six weeks but added three
additional training sessions per week. One group performed extra track running and the other exercised on a bicycle ergometer. Work intensities and durations were similar for both groups in the added sessions. A further control group (N = 10) was formed. A variety of physiological and blood measures were taken and a time trial over five kilometers was performed before the training commenced, in the middle of the period, and after completion.
The training groups benefited from the training experience, changing or improving in most measures. However, there were no differences between the two training groups.
Cross training provided no extra benefit for
performance over that gained from additional specific running training.
Implication. Extra cycling training in a running group provides no further benefit to running performance than does extra running over a short-duration such as six weeks.