Alex Hutchinson explains how to hold on to your sprint speed as you age:
Many of the challenges of daily living, once you hit your 70s and 80s and beyond, are essentially tests of all-out power rather than sustained endurance (though both are important).
The problem is that sprint speed starts declining after your 20s, and most endurance athletes have no clue how to preserve it.
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Older sprinters take shorter steps and their feet spend longer in contact with the ground, presumably because they’re less able to generate explosive force with each step. That’s consistent with the finding that older sprinters have less muscle, and in particular less fast-twitch muscle, than younger sprinters.
But it’s not just a question of how much muscle you’ve got. In fact, some studies suggest that you lose strength more rapidly than you lose muscle, which means that the quality of your remaining muscle is reduced. There are a bunch of different reasons for muscle quality to decline, including the properties of the muscle fibers themselves, but the most interesting culprit is the neuromuscular system: the signals from brain to muscle get garbled.
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The authors cover their bases by recommending that your resistance training routine should include workouts that aim to build muscle size (e.g. three sets of ten reps at 70 percent of one-rep max); workouts that aim to build strength (e.g. two to four sets of four to six reps at 85 percent of max); and workouts to build power (e.g. three sets of three to ten reps at 35 to 60 percent of max).
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The authors suggest training to improve coordination through exercises that challenge balance, stability, and reflexes, such as single-leg balance drills. One advantage of this type of training: it’s not as draining as typical “reps to failure” strength workouts, so it may provide more bang for your buck if you can’t handle as many intense workouts as you used to.
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On that note, the standard advice that veteran athletes give you when you hit your 40s is that you can no longer recover as quickly. Strangely, the authors point out, the relatively sparse data on this question doesn’t find any differences in physiological markers of post-workout recovery between younger and older athletes. The main difference is that older athletes feel less recovered—and in this case, it’s probably worth assuming that those feelings represent some kind of reality, even if we don’t know how to measure it.