You probably know the many benefits you gain from running and weightlifting—and following a consistent routine that incorporates the two. But sometimes, especially after a heavy leg day workout, your body can feel pretty tired and sore and seemingly not ready to take on miles. This isn’t just in your head, either. According to a review of 132 studies, it takes a full day or two more to recover from resistance training than it does a high-intensity run.
If you’ve ever been tempted to skip the weights today in favor of a better run tomorrow, it’s important to consider the advantages of strength training. Not only does it just feel good to move your muscles through full ranges of motion, especially after sitting all day, but it can also pay off in the long run for your performance and overall health. In fact, several studies point to better running economy, as well as VO2 max and anaerobic threshold, when following a program that incorporates both endurance training and strength training.
So, instead of ditching strength exercises to focus on mileage, the key is optimizing your running and weightlifting program. After all, strength training is supposed to help, not harm, your running. Here’s how to achieve that.
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The Background on Running and Weightlifting
To get it right, you need to understand how your body reacts to moving heavy stuff. Picture pushing a hand truck 50 feet. Pretty easy. That’s running—your body is the hand truck and it moves its own weight rather effortlessly. Now slide the hand truck under a fridge and push it just five feet. A lot more difficult. That’s mechanical loading; it’s why 10 heavy squats feels so much more challenging than 1,000 foot strikes.
The reason strength training makes you faster is because it lowers the amount of energy required to hit a certain pace, explains Kenji Doma, Ph.D., a sports and exercise scientist at James Cook University in Queensland, Australia, and author of a 2014 study on strength training and running performance published in the European Journal of Sports Science. He has also studied the effects of combining aerobic exercise and strength training on muscle hypertrophy and strength, as published in a Sports Medicine systematic review and meta-analysis in 2022. (The researchers found that combining the two types of training doesn’t hinder strength and muscle-building gains, but can compromise explosive strength gains when performed in the same session—something to consider if that’s your goal.)
What’s important to note is that when you lift weights, your brain alters its neural recruitment pattern, calling up the most fatigue-resistant muscle fibers so you exert less energy. That’s why you don’t want to skimp on strength training. Doma’s research offers guidance on how best to combine mile repeats and repetitions in the gym for a more well-rounded running and weightlifting program.
The Research on How to Combine Running and Weightlifting
In the study that focused specifically on running performance, fifteen runners of a wide range of ability and average weekly mileage did different strength-training sessions on three occasions. One workout was a high-intensity, total-body session, one was high intensity but for legs only, and one was a low-intensity, total-body workout.
Six hours after each workout, the runners did a treadmill test for 10 minutes at 70 percent of ventilatory threshold pace (easy), then 10 minutes at 90 percent of threshold pace (roughly close to half marathon pace), and then as long as possible at 110 percent of threshold pace. The runners also did the treadmill test at the outset of the study, to get a benchmark for how they would perform when fresh.
The high-intensity strength workouts significantly lessened the runners’ time to exhaustion at the end of the treadmill test. In the benchmark test, they’d lasted an average of close to 5 minutes at 110 percent of threshold pace. After each of the high-intensity strength sessions, time to exhaustion was almost a minute less, suggesting that the hard weight workouts six hours earlier had dramatically decreased the runners’ ability to sustain fast running.
How to Apply the Science to Your Own Running and Weightlifting Workouts
Doma says his findings have practical implications for how runners should arrange their workouts.
First, he advises not to schedule a hard running workout later in the day of a weight session. “Running at maximal effort is impaired six hours [after] lower-extremity resistance training, and therefore trained to moderately-trained runners will need more than that to recover for running sessions set at high intensities,” he says.
Plus, running at maximal effort is still impaired 24 hours after lower-extremity resistance training, according to Doma. “Therefore, in the case of trained and moderately-trained runners undertaking high-intensity running sessions after lower-extremity resistance training, they may need more than one day to recover.”
Doma also found that running performance at lower intensities was unaffected by the weight workouts. “Runners could undertake strength training and running sessions on the same day six hours apart as long as the running session is set at submaximal intensities,” Doma says. In other words, if you have an easy, long run or recovery run on the schedule, it’ll be fine to double up that day, as long as workouts are over six hours apart.
If possible, Doma suggests arranging your schedule so that on days that you run and lift, running comes first. “I found that lower-extremity resistance training performed six hours prior to running sessions at moderate to high intensities cause carryover effects of fatigue the next day to a greater extent than the reverse sequence,” he says. “Therefore, if undertaking lower-extremity resistance training and running sessions on the same day, it is best to undertake a running session before a strength training session. For example, running in the morning before work and lower-extremity resistance training in the evening after work.”
In this scenario, it would make sense to have that morning run be one of your harder workouts of the week. Your workout the following day would then be an easy recovery run, which would be warranted even without the evening lifting, but is that much more called for on the basis of Doma’s research.
This sequence would also mesh with many coaches’ recommendation to have great discrepancy between your hard and easy days, so that you can better recover from your toughest workouts—instead of including hard elements of non-running training on your easy running days.
Sample of a Running and Weightlifting Weekly Program
- Day 1: Light resistance training with a focus on upper body
- Day 2: Tempo run (run at an 8 out of 10 effort for approximately 20 minutes)
- Day 3: Easy run in the morning; heavy resistance training with a focus on lower body in the evening
- Day 4: Off
- Day 5: Tempo Run
- Day 6: Easy Run
- Day 7: Long Run
Scott is a veteran running, fitness, and health journalist who has held senior editorial positions at Runner’s World and Running Times. Much of his writing translates sport science research and elite best practices into practical guidance for everyday athletes. He is the author or coauthor of several running books, including Running Is My Therapy, Advanced Marathoning, and Meb for Mortals. Scott has also written about running for Slate, The Atlantic, the Washington Post, and other members of the sedentary media. His lifetime running odometer is past 110,000 miles, but he’s as much in love as ever.
A former Division 1 runner, Dan grew up riding fixies and mountain bikes and now reviews everything from performance running shoes to road and cross bikes, to the latest tech for runners and cyclists at Bicycling and Runner’s World.
