For Fitness, Intensity Matters

This year, exercise science expanded and fine-tuned our understanding of how physical activity affects our brains, joints,hearts, and even genes, beginning before birth and continuing throughout our lifespans, which can be lengthened, it seems, by exercise, especially if we pick up the pace.
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But the lesson that seemed to emerge most persistently from the fitness-related studies published this year was that intensity matters, especially if you wish to complete your workout quickly. The most popular column that I wrote this year, by a wide margin, detailed “The Scientific 7-Minute Workout,” a concept that appealed, I have no doubt, because the time commitment was so slight. But the vigor required was considerable; to gain health benefits from those seven minutes, you needed to maintain a thumping heart rate and spray sweat droplets around the room.

Almost halving the time spent exercising was also effective, a later and likewise popular column showed. In that study, out-of-shape volunteers who ran on a treadmill for a mere four minutes three times a week for 10 weeks raised their maximal oxygen uptake, or endurance capacity, by about 10 percent and significantly improved their blood sugar control and blood pressure profiles.

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