These alternative forms of exercise benefit the running wounded and healthy runners alike.

There’s no worse feeling in the world than being unable to train due to injury, especially when you’ve been told by a medical professional to simply “stop running” until the injury heals. However, taking total rest is one of the worst things you can do when trying to rehabilitate an injury. If you can’t run and you’ve got your sites set on speeding up the recovery process and staying fit until you’re back on your feet again, then it’s best to stop sulking and get your banged-up body moving again as soon as possible.

Let’s take a look at three of the most effective cross-training options for runners looking to maintain fitness while overcoming an injury, or better yet, to avoid injury altogether.

Alter-G Treadmill

Training on an Alter-G antigravity treadmill allows you to replicate your running workouts at a fraction of your body weight, meaning you can reap almost all of the same fitness benefits without the same type of wear and tear on your body. Of course, for most runners, access to one of these incredible machines is limited, but if you’re injured and there’s an Alter-G in your neck of the woods, it’s worth renting out once or twice a week if you want to salvage your hard-earned fitness and return to running on land as quickly as possible.

In my own experience recovering from a stress fracture on my pubic symphysis two years ago, I was able to start running twice a week on the Alter-G soon after the injury was diagnosed, starting at 65 percent of my body weight and working my way up to 90 percent over the course of 10 weeks. In combination with copious amounts of cycling and core work, running interval workouts and tempo runs on the Alter-G allowed me to train hard while my injury healed and also helped me to resume running on land four weeks sooner than anyone, myself included, thought possible.

The Alter-G isn’t just for the injured amongst us, however. Andrew Middleton, an Olympic Trials Marathon qualifier, utilizes the Alter-G even when he’s healthy in order to give his body a break from the wear and tear of running a lot of miles in training.

“After 26- to 28-mile-long runs and 15-mile tempo runs my body will feel quite worn down the next day,” he says. “From past experience I have learned not to push my body on these days. So, by utilizing the Alter-G to lower my body weight to 90-93 percent I can limit the pounding on my legs, thus allowing for quicker recovery while still getting the aerobic benefit. One of the key ideas I adhere to in training is the better you recover, the better you will run.”

Water Running

Contrary to popular perception, the pool isn’t just for streamlined swimmers and old ladies doing water aerobics. It can be an injured runner’s playground and is perhaps the safest option for cross-training through many impact-related injuries.

Of course, if you’ve ever treaded water for more than 5 minutes in the deep end of a pool, you know it’s an exercise in monotony as much as it is an excellent aerobic workout. The good news is that there’s no impact on the body, so you can run in the water for as long you would run on land and perform hard workouts almost daily with no concern for aggravating an existing injury. This is important because not only will intense interval sessions keep you fit while you overcome your injury, but they will also keep you from losing your mind as time seems to stand still.

In the pool, short intervals from 30 seconds to 3 minutes with half to equal rest will give you the most bang for your buck. Because of the resistance provided by the water, your turnover will be slow but be sure to drive your knees in a sprinting-like fashion to keep your heart rate elevated. Even so, your heart rate will be lower than when running on land, so use perceived exertion to gauge your effort in the water. Wearing an aqua jogging belt is best for beginners and encourages proper form, while water running without a belt provides a better total body workout and demands a little more focus to maintain good form.

In addition to running in deep water to maintain fitness, I’ve used the shallow end of a swimming pool to fine-tune my form without the risk of unnecessary impact by performing a few sets of basic drills such as high knees, butt kicks, bounds and fast feet. Because of the reduced speed in the water, 15 meters worth of work for each drill is fine, but be sure to keep the intensity high and focus on covering ground with fluid form throughout the session.

Spinning

While outdoor riding is fast and fun, it doesn’t translate very well to retaining running fitness. If you’re injured and don’t have access to an Alter G treadmill or swimming pool, setting your bike up on a trainer or signing up for a spin class at your local gym is the next best way to rev your aerobic engine. Staying stationary for an hour or more in a controlled environment can be mind numbing, but it’s far more effective at replicating running workouts than dealing with the incessant interruptions of road cycling.

I’ve found that my spinning sessions need to be one-and-a-half times longer than my usual running workouts to achieve a similar stimulus. So, for example, to replicate a 60-minute recovery run on the roads I’ll spin for 90 minutes at an equivalent effort. Sometimes I’ll use a heart-rate monitor to keep tabs on myself, finding that my heart rate is usually about 15 beats per minute lower on the bike than when running. For harder efforts such as interval sessions and tempo runs, the same principle applies: 3:00 intervals at 5K effort get bumped up to 4:30 at an equivalent effort or heart rate; a typical 30-minute tempo run on the roads is 45 minutes at the same effort on the bike.

For my own training, as well as with the athletes I coach, I prefer the use of a spin bike for specific sessions rather than a bike trainer because the resistance can easily be controlled and you can get out of the saddle to replicate a running motion when doing intervals. I’ll have athletes work mostly at a low to medium resistance and keep a high cadence (90-100 RPM) to engage the right running muscles and maintain good turnover.

The absence of impact in spinning facilitates a quick recovery and allows you to go harder more often than you could or should when running. While rehabbing my way through a case of posterior tibial tendinitis less than six weeks out from the 2008 Boston Marathon, I literally spun my way to the starting line, mixing up interval workouts and tempo “runs” on the bike every other day for three weeks (zero running!) to maintain my hard-earned fitness. In the end, I finished less than two minutes off my personal best and have been a big believer in the benefits of spinning ever since.