Eight students cycled four to six times for 30-seconds separated by four minutes of recovery daily, while the other group cycled for 90 to 120 minutes each day. At the end of the two weeks, the first group had only exercised 2.5 hours total, and the second group had performed 10.5 hours of training. Yet both groups showed similar health improvements.
Participants of both groups had similar muscle glycogen contents. Glycogen is a sugar molecule that is readily converted to glucose to supply the body with energy during heavy work. Synthesis of glycogen is usually greater after exercise. The researchers also found that improvements in muscle parameters associated with fatigue resistance were similar in all subjects.
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