For runners in search of personal bests and top fitness, the fundamental elements of training—frequency, duration and intensity—must be considered. Put simply, to perform at your best, you must run regularly, put in adequate mileage, and complete harder workouts. Frequency is where the one-time-per-week approach falls apart. While you may be able to finish a 5K or 10K off minimal training, you won't be able to perform optimally.
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How Often You Run Counts More Than How Long You Run
Frequency is so important for overall fitness that Malmstrom recommends three shorter runs of 3 x 20 minutes per week over one 60-minute run.
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"That would mean that the individual exercises on three days per week instead of just one, enabling all of the beneficial responses to exercise, including an increase in growth hormone, a 'fat-burning hormone,' on more days of the week," she contends. "The person who runs only once per week as the only exercise he or she gets will have fewer days of that growth hormone increase, and may, in fact, increase his or her cortisol or stress and fat-storing hormone."
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If, however, you're running once a week in conjunction with other workouts, you'll garner the benefits of exercise with less pounding. Combining running with activities like yoga and cycling can help boost all-around strength, flexibility and endurance better than running alone. This is why even high mileage running programs recommend cross-training and other supplementary work to help build overall fitness.
Malmstrom emphasizes that if it's not just fitness, but a boost in running performance that you're interested in, you must run. "It's a good idea for all runners who are serious about running to run on more than one day per week to maximize the benefits of running and also decrease the risk of injury."
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To be sure, the Principle of Specificity states that you must practice a certain activity to get better at it. So if you're looking to compete in a race, rather than simply complete it, you must put in adequate mileage to do so optimally. While many cross-training activities simulate similar cardiovascular gains, technical running skills can only be garnered by actually running.
"If we do not train appropriately and take short cuts, it only leads us closer to potential injuries," adds Malmstrom. "In order to be a better runner, one must train with proper frequency, intensity and duration."
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With that said, if you are only in search of the most basic health benefits, the most recent research suggests: "Running, even 5 to 10 minutes per day at slow speeds, less than 6 miles per hour, is associated with reduced risks of death from all causes and cardiovascular disease."
While every runner requires a slightly different approach to training depending on the distance, injury history and time available to train, you should plan on trying to fit in more than one run per week. Not only will you feel better during training thanks to the mood-boosting effects of running, but you'll also perform better, rev your metabolism and ward off potential injuries.
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