Would you want to enhance your working? Deal with recreation.

Last fall, we (Outside) collaborated with WHOOP, the 24/7 fitness tracker, to develop Project PR, a 5K training program with the simple goal of better understanding how recreational training can help keep runners healthy stay and improve their skills performance. It was a huge success – nearly 2,500 participants completed the training and after eight weeks the results told a compelling story about the relationship between training, recovery and performance. Here is everything you need to know about this unique study.

The motivation

Injuries are an unfortunate and all too common reality for runners – up to 75 percent of all runners are injured each year. The most common culprit: overtraining. Unless you’re just slowing down and affecting your stamina, running too many miles with too little rest can lead to a range of problems ranging from hormonal imbalances to shin splints and tendon strain. Understanding when to skip a run instead of asserting yourself is key to avoiding injury and becoming a more consistent, faster runner.

This is where WHOOP comes in. The sleek, wrist-worn heart rate monitor calculates three key metrics – exercise, recovery, and sleep – to give users a comprehensive view of their daily physiology. The most important part is that WHOOP is tailored to each user and is constantly evolving with him or her. As fitness improves over time, WHOOP has the data to prove it. Conversely, if performance declines due to injury, illness or overtraining, WHOOP will also track this. The real magic lies in the WHOOP recovery algorithm, which offers users an easy-to-understand recovery value based on subtle changes in heart rate variability, resting heart rate and sleep performance.

How it worked

All Project PR participants completed a training program designed by professional runners Nick Willis and Mary Cain. It started with a 5k baseline and ended in a final time trial. After the initial breakdown into categories by skill level (beginner, intermediate, advanced), the participants in each category were further divided into three groups, each with their own method of following this program.

Participants in so-called “WHOOP Dynamic Groups” modulated their training based on the feedback from their WHOOP wearers. In particular, when the participants’ recovery values ​​reached 67 percent and more, they were given the green light to take on the planned workouts for the day. A recovery score between 34 and 66 percent – the yellow zone – meant runners should reduce the duration and intensity of their training. Less than 33 percent were instructed to reduce the duration and intensity of their training even more.

The runners in the second group were “static participants” who used the training plan and a WHOOP sling, but did not modulate their training based on their recovery scores. The third group was the control group that did not use WHOOP at all. All participants logged their runs on Strava to verify compliance, and those in the two WHOOP groups logged the data recorded by their devices on a daily basis.

The results: less work, improved performance, fewer injuries

Many of the participants in the dynamic WHOOP group had experiences like that of Jennifer Baskerville-Burrows, a 54-year-old Indiana bishop who raced and trained all the time but only got five to seven hours of sleep a night – a formula that always worked back to secondary injuries. Baskerville-Burrows was unhappy about missing out on what she loved to do and decided to sign up for Project PR. Recalibrating her training and recovery based on the data provided by her WHOOP changed the game.

“For the first time in a long time, I slept seven to eight hours consistently every night because I was focused on making this a priority,” she says. And by the end of eight weeks, she threw off a full minute of her 3 miles. “Learning how to exercise and taking care of my recovery made all the difference.”

Dylan Metsch-Ampel, a 23-year-old paralegal from New York who was also part of the dynamic group at Project PR, had similar benefits and was able to shave three minutes before his previous personal 3-mile record. “What surprised me was how quickly my body adjusted to the higher weekly mileage over the course of the plan,” he says. “I found that I was more tired at the end of the day, but tried to get to bed earlier and earlier so I could relax and run the next day.”


These improvements are commendable and not outliers. On average, participants in each training group in the program saw similar increases. It gets interesting when you consider how much work it takes to make those gains – and how high the injury rate is along the way.

Compared to members of the static group and the control group, the participants in the dynamic WHOOP group exercised less (at least 10 percent less) and achieved comparable improvements. For example, on a day when their recovery values ​​were yellow or red, they would do 15 to 20 minutes less work than a green recovery value. Equally remarkable is the fact that the injury rates in the static group, in which runners covered more kilometers with greater effort than in the dynamic group, were 30 percent higher. In other words, the old adage “work smarter, not harder” definitely means mileage.

In the follow-up survey of the project’s PR participants, 80 percent of respondents said they were motivated to complete their training sessions during the program. In the dynamic group the number went even higher. “All together, it was the secret sauce for me,” says Baskerville-Burrows. “The other day I jumped out of bed and down the stairs and realized I hadn’t done that in a few years.”

Recovery is clearly training. Would you like to see some low injury / high recovery / better speed results for yourself? The full results of Project PR can be found here. Then grab a WHOOP and use its valuable feedback to help you decide whether to go for that scheduled run or hit snooze.


WHOOP uniquely combines hardware, software and industry-leading accurate measurements to help people push the boundaries of fitness and performance, create powerful behavioral changes, and enable them to optimize all facets of life. WHOOP membership includes a free WHOOP Strap 3.0 for 24/7 actionable insights and health coaching.

Related Articles