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In the early days of modern athletics, runners had few choices—and little awareness—when it came to injuries. For the most part, they could either rest or train through it. Today, we are fortunate to have thousands of resources to aid in our every ache and pain. Personally, I would debate that the foam roller is indeed the best invention since sliced bread. Even so, it’s true that rolling out can’t fix a major injury—at least not alone. And when running isn’t an immediate option, many athletes turn to water—specifically, the underwater treadmill.
The concept is fairly simple: If you are coming back from an injury or are experiencing muscle pain, your body might not do well with full-weight-bearing activity. Similar to an anti-gravity treadmill, an underwater treadmill allows you to run at a lower percentage of your body weight. It reduces the impact of running and increases the resistance, meaning you can still get a decent workout in despite the fact that you aren’t running on land.
Underwater treadmills are often built into physical therapy pools, which gives the pool multiple uses while allowing a section for the treadmill belt at the bottom. There are also portable underwater treadmills that are significantly less expensive, starting around $1,500. As a comparison, a high-end underwater treadmill will set you back $80,000 or more.
The use of underwater treadmills at physical therapy centers is common, but what if you aren’t rehabbing your injury at a physical therapy center? If you don’t have a pile of cash lying around to buy a treadmill, you’re in luck. There are plenty of ways to mimic the benefits of the underwater treadmill without sacrificing your retirement fund.
If you have access to a shallow pool, you can run laps around the perimeter, weighing yourself down with an old pair of shoes if necessary. No pool? You can also run laps around a hot tub, though I would advise turning the heat off and generally taking caution against hot temperatures. If done correctly, your water running will work up a sweat, and you won’t want to overheat.
Whether you use a legitimate underwater treadmill or create your own water-running routine, the key is progression. Start with a short amount of time (five or 10 minutes) and slowly increase the time you spend running in the water, so long as you don’t feel pain. After consistent use of the underwater treadmill—with no pain—you can graduate to land running, so long as you and your doctor agree that your legs are ready.
The underwater treadmill is a great cross training option—whether you’re injured or not. Running underwater can strengthen your muscles and promote healing from injury. It can also be more enjoyable than hours spent on a stationary bike and, hopefully, will get you back to running on land.