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Can’t afford an antigravity treadmill? Try this instead.
Written by: Matt Fitzgerald
The typical elite runner spends no more than 15 hours per week running. Compare that to the 30 hours per week that the typical elite cyclist spends on his bike. Why do cyclists ride twice as much as runners run? Because they can.
Running is much more stressful to the musculoskeletal system than other endurance activities. Tolerance to this stress is the primary limiter to training volume for most runners. Our legs have had all they can take long before our heart and lungs have.
Many runners supplement their running with low-impact and non-impact forms of cardiovascular training as a way to give their heart, lungs, etc. additional training stimulus without subjecting the legs to more stress than they can tolerate. For example, Australian elite runner Andrew Letherby rides a bike 150 miles per week in addition to running 70 to 80 miles. That’s an extreme example, but there are countless other examples of other elite runners who supplement their running with a little cycling, elliptical training, pool running, or whatever.
The only problem with bicycling to improve your running is that bicycling is not running. Time spent on a bicycle (or elliptical trainer or whatever) does not improve running performance as much as time spent running does. Some non-running activities are more similar to running than others, however. It’s important to choose running alternatives whose fitness benefits carry over to running especially well. For example, cycling is a better choice than swimming.
The ultimate running alternative, in my opinion, is the Alter-G antigravity treadmill. Unlike other activities, running on an Alter-G is not an alternative to running, it is running, except at a technologically reduced body weight that reduces stress on the legs. Time spent running on an Alter-G undoubtedly improves running performance more than time spent doing any other non-running activity, yet it does not increase injury risk any more than bicycling and the other alternatives.
The downside of the Alter-G is that it’s very expensive and not very accessible for most runners. So what’s the next best thing? I believe it’s steep uphill walking on a treadmill. Research has shown that when individuals walk up a steep incline at a brisk pace, their brains use the same motor pattern that they use to run at the same speed on the same grade. In other words, at a given speed, there’s a certain gradient at which the difference between walking and running disappears. That’s significant, because it’s primarily the motor pattern that the brain uses to produce a given type of aerobic activity that determines how much the cardiovascular benefits carry over to running. Therefore, walking briskly on a steep incline stands to improve your running almost as much as running itself. Yet walking is a low-impact activity, especially when it’s done on a steep grade. So supplementing your running with steep uphill walking on a treadmill won’t increase your injury risk any more than using an elliptical trainer will.
Here’s how to do it: Set a treadmill at a 15 percent incline, which is maximum on most models. Start walking and increase the belt speed until there’s really no difference between walking and running, but think “walking,” because you want to do this workout at the minimum speed at which the difference between walking and running disappears. Continue at a steady pace for as little as 20 minutes or as long as an hour, depending on your training needs that day.
You can incorporate steep uphill treadmill walking into your training in a number of ways. One option is to do it once a week as a recovery workout, perhaps the day after a long run, as an alternative to taking the day off. Or you can do several sessions per week to significantly boost your overall aerobic training volume. For example, you could run in the morning and walk in the evening on most days of the week. You can also make steep uphill treadmill walking your sole form of aerobic exercise when you’re injured and can’t run, provided your specific injury doesn’t keep you from walking too.
One word of caution: Steep uphill walking puts a fair amount of stress on the calves and Achilles tendons, so you’ll want to ease into it and avoid switching over to it abruptly when a running injury occurs. If you plan to walk daily when running injuries do occur, then do at least one steep uphill treadmill walk per week routinely before you get injured so that your body is already adapted to the activity when an injury occurs and you transition to daily walking.
Check out Matt’s latest book, Racing Weight Quick-Start Guide: A 4-Week Weight-Loss Plan for Endurance Athletes.