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It doesn’t take a research experiment to prove that aerobic fitness is important. Without input from scientists, coaches (and self-coached athletes) frequently recommend training right between the barrier of hard breathing and uncontrollable gasping — the spot where the body’s aerobic fitness is working at near full capacity — to boost aerobic fitness. But researchers at Rennes 2 University in France have found that the type of recovery taken between intervals is also important.
They trained two groups of new runners with interval workouts made up of the same hard sections, but with different recovery.
VO2 is shorthand for volume of oxygen. VO2 max is the most oxygen a person can consume and is a common (although imperfect) way to measure aerobic fitness.
For short-course triathletes who don’t fit into the “elite” wave, VO2 max is a strong indicator of performance, according to a study performed at the University of Tennessee. The right kind of training can boost this all-important number.
Group 1: Standing Recovery
30×30 seconds hard, 30 seconds standing
Result: No change to VO2 max
Group 2: Running Recovery
20×30 seconds hard, 30 seconds slow jog
Result: Improved VO2 max baseline
Despite running fewer intervals, the athletes who ran between repeats upped their aerobic fitness more than those who stood for recovery. If interval workouts with short repeats are part of your training plan, jog between repeats for a meaningful fitness boost.
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