Q: What is interval training?
A: Interval training involves alternating short bursts of intense and moderate aerobic exercise. For example, you cycle very hard for two minutes, then pedal for two minutes at a more relaxed pace, then speed up again, and so on.
Studies have found that interval training can improve aerobic fitness better than moderate-intensity workouts at a steady pace, and in less time. And it can help control blood sugar, lower blood pressure and raise HDL (“good”) cholesterol. Interval training helps improve the efficiency and endurance of muscles by making them alternate between aerobic exertion (in which oxygen is used to generate energy) and anaerobic exertion (without oxygen). The recovery periods also allow for the removal of some lactic acid that accumulates in the muscles and makes them tire.
Here’s how to get started. If you run, for instance, just speed up for one to four minutes, then slow down for a similar period, then alternate. You can increase the length or intensity of the strenuous bouts and also vary the length of the slower bouts. See what works best for you.
Ideally, the intense bouts should get your heart rate up to 85 to 90 percent of its maximum. You need not “go all out,” however, unless you’re an athlete or at least very fit. During the recovery periods, try not to let your heart rate drop below 60 percent of its maximum.