interval training

Interval training is a type of exercise that alternates exercise (or “work”) and recovery (or “rest”) periods.

For example, row hard for 30 seconds, then an easy pace for 30 seconds for 20 rounds. This can also be done with distance; sprint to an obstacle, then walk or lightly jog back to the starting point repetively.

https://en.wikipedia.org/wiki/Interval_training

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