Do Runners Need Cross-Training?

What's the "best" form of cross-training for runners, and who actually benefits?

Some runners swear by cross-training, while others view it as a waste of time. The usefulness of effective cross-training rests somewhere in between these two extremes. Cross-training is beneficial for certain runners in certain scenarios. This article will examine when cross-training is useful, as well as which modes of cross-training are most specific to running.

For the sake of this article, we will define cross-training as an aerobic training modality with lower impact than running. Strength training, Pilates, and yoga do not provide a significant aerobic stimulus and therefore do not count as cross-training. Strength training is resistance/anaerobic training, while Pilates and yoga are forms of flexibility and mobility training.

Does Cross-training Prevent Injury?

Some runners will claim they got injured because they didn’t cross-train enough. How true is this belief?

Cross-training is not inherently protective against running-related injuries for all runners. Running-related injuries fall into two categories: acute and overuse. Acute injuries include sprains and strains: a rolled ankle, a pulled hamstring, or a similar injury that occurs suddenly during a run. Overuse injuries occur when tissue is unable to tolerate load over a longer period of time: a bone stress injury, tendinopathy, and the like.

A majority of running-related injuries are overuse injuries. Overuse injuries stem from poor load management, inadequate recovery, atypical mechanics, or a combination of these factors. While cross-training can reduce biomechanical loading, it will not protect against overuse injury if load is poorly managed, recovery is inadequate, or a biomechanical irregularity is present.

Cross-training can play a role in load management, especially for runners with a history of injury, novice runners, or masters runners. These athletes may be able to run only three or four days without increased injury risk or poor recovery. If these athletes want to increase their training volume, they will benefit from cross-training.

In coaching, I sometimes use cross-training as a way to increase training intensity for injury-prone athletes. If they can only handle one hard running workout, with limited time at intensity, then the bike or elliptical provide them with the ability to safely increase training intensity. For some 70+ runners, the elliptical or bike may be the only form of intensity, while all runs are kept at an easy pace.

However, throwing multiple cycling sessions on top of five to six days of running per week won’t prevent injury - that approach will actually increase training load and recovery demands. For cross-training to actually reduce impact and reduce tissue loading, you need to replace one to two runs per week with cross-training sessions.

Cross-training When Injured

Despite what you see on Instagram, multiple hours of elliptical or bike per day are not an appropriate training plan while injured. Excessive cross-training can delay return to running and potentially increase your risk of a future injury (or return of the same injury).

Running-related injuries need energy to heal. If you are in a caloric deficit and not consuming enough protein, your recovery will be compromised. It’s difficult to eat enough for bone stress injury recovery if you are spending three hours a day on the elliptical.

That said, complete rest is seldom the most appropriate approach during injury. After the acute stage (the first week of an injury), appropriately dosed, low-impact loading can aid in tissue recovery. You’ll maintain your fitness and have a smoother recovery time with 30-60 minutes of cross-training a few times per week. Since resistance training is crucial for recovery from tendinopathy and other injuries, you need to allot two to three days per week to include resistance training. Aerobic cross-training should not be a priority over resistance training when recovering from an injury.

Do I Need to Cross-Train If Not Injured?

For healthy runners without significant injury history, swapping out runs for cross-training will have little impact on their injury risk. Their tissues can tolerate ground impact forces well, especially if the athlete has a well-balanced training load.

Older seminal research demonstrates that cross-training adaptations never exceed those of the primary sport. The adaptations of cross-training will never improve your running better than any running you can safely handle.

If you are training for a race such as a marathon, you can’t shortcut run training by doing a large amount of cross-training and minimal running. If you enjoy swimming, skiing, or even cycling more than the running required to do a marathon, then be honest with yourself about it. It’s okay if running is your cross-training for another sport.

The Best Cross-training When Injured or Injury-Prone

One key principle for training is specificity. Training should support the cardiovascular, neuromuscular, and mechanical demands of the primary sport. When you are cross-training due to an acute injury or reduced recovery capability, you ideally want to choose cross-training modalities specific to running. The greater the specificity, the higher the rate of transfer to running.

Therefore, cross-training should mimic, to some degree, the cardiac output, biomechanical patterns, and neuromuscular recruitment of running. The most specific modalities of cross-training for runners are pool running, elliptical/arc trainer, and cycling. Each can produce high cardiac output and mimic the movement patterns and neural recruitment of running, with various degrees of impact.

Pool running (sometimes also called aqua jogging) involves locomoting around the pool in an exaggerated running form. A floatation belt removes all impact; feet should not touch the pool floor.

Since pool running includes a high knee drive and exaggerated arm swing, the neuromuscular activation patterns, range of motion, and muscle use are all highly similar to running. While the cold water may artificially depress heart rate, runners can achieve a similar rate of perceived exertion (RPE) to outdoor running. Due to the low impact, intervals can be used in most sessions to modulate intensity.

While some arguments can be made that pool running is the most specific, it also doesn’t rank as high in accessibility. Pool running requires pool access, which may not come with all gym memberships. The time cost of pool running can be higher (especially if going to the pool during peak hours), which may make it less desirable for time-limited athletes.

The elliptical and arc trainers are both stationary, low-impact cross-training machines. The machines differ in the foot pedal patterns, with an elliptical moving in an elliptical/oval motion and an arc trainer in a gliding motion.

Both machines are specific to running. Since you are in a standing position, heart rate and oxygen consumption rates are similar to running at the same RPE. Both machines produce similar movement patterns in the hips and legs, and mimic arm swing if you use the handles. If you achieve the same cadence as with running, then the neuromuscular recruitment patterns are similar. Impact on the joints is low, and ground impact forces are non-existent.

One advantage of the elliptical and arc trainer are the accessibility. Virtually all gyms have these machines. Even in a high-cost-of-living area, you can purchase a Planet Fitness membership for $15USD per month. (The same cannot be said for the ElliptiGo, which is more comparable to a mortgage for an item that requires a large garage to store.)

Both indoor and outdoor cycling are popular forms of cross-training. Muscle patterns diverge slightly from running, since cycling is more quad-dominant than running. The calf and gluteal muscles are recruited less for cycling, although indoor cycling may recruit these more with out-of-saddle intervals.

Outdoor cycling typically requires a longer session to produce a similar aerobic stimulus as running, due to periods of coasting. However, it does allow runners to spend time outdoors when injured. Although if you have an injury that could worsen with a cycling collision (such as a sacral stress fracture), proceed with caution. Cycling has its own exercise economy, so you won’t see transference to running economy as you would from pool running or the elliptical.

Indoor cycling, such as using the Peloton or Zwift, has higher oxygen consumption rates in a shorter period of time than outdoor cycling. Indoor cycling workouts never include coasting; you are always pedaling. If you maintain a cadence similar to running (85-95 rpm), you will receive transferable neuromuscular benefits.

Enjoyment and adherence are important variables. Cross-training isn’t effective if you frequently skip or shorten sessions. In coaching, I have observed that many runners report higher adherence to cycling, whether due to enjoyment or at-home equipment.

Cross-training does reduce the ground impact forces of running. However, not all modalities are equal in terms of their impact. Pool running has virtually no impact, which means it may be more appropriate when initially recovering from a bone stress injury. The elliptical provides 60% lower impact than running, which makes it useful later in a rehab process for certain injuries.

While swimming provides an excellent aerobic stimulus, the transfer to running is moderate at best. Experienced swimmers may be able to swim long enough for a productive aerobic stimulus. However, inexperienced swimmers (such as myself) may be technically limited. Even for an experienced swimmer, the horizontal position and upper body dominance aren’t as specific to running as other modalities. If you don’t particularly enjoy swimming or have good technique, you will benefit more from pool running or the elliptical.

The Other Category: Cross-training for Fun

Many runners engage in non-running aerobic activities simply because they enjoy them. Runners often feel like they need to justify time spent not running, but if you enjoy an activity, just let yourself enjoy it, whether or not it significantly improves your running.

A lot of non-specific cross-training falls into this category: hiking, swimming, Nordic skiing, downhill skiing, etc. The specificity to running may not be high, and that’s okay. These are activities that are worth enjoying in their own right. (That said, hiking may be beneficial for some ultra runners.)

Likewise, these activities have greater equipment, environmental, and financial limitations that make them less accessible and desirable for a runner who just wants to lower injury risk. (As someone who’s had as many hiking injuries as running injuries, I’d argue that many outdoor sports come with their own injury risk.) For example, Nordic skiing requires expensive equipment and weather conditions that only occur for a few months of the year. While a fun winter sport, it is not practical or effective cross-training for a runner who needs to supplement their training year-round.

As a runner with a limited injury history, my cross-training falls into this category. I hike, ski, and snowshoe because I enjoy them. While I did run my fastest races when I frequently participated in these activities, this was likely due to also being able to do more running. While my slower race times in 2022-2024 corresponded with less hiking and skiing, those weren’t due to the lack of these sports. Rather, I hiked and skiied less for the same reasons I trained less: the merry-go-round of preschool/kindergarten illnesses and worse recovery at high altitude.

Some runners prefer to let their favorite non-running activities cycle with a running focus. They may opt for a running off-season in winter, with lower volume and intensity, so that they can enjoy skiing more. You won’t lose fitness with this approach - if anything, you gain enjoyment.

References:

• PMID: 32881840

• PMID: 20453685

• PMID: 26950347

• PMID: 7871294

• PMID: 19290675

• PMID: 23015879