Tom Holland’s ‘Cindy’ Will Make You a Better Outdoor Athlete

For seasoned outdoor athletes, a 20-minute bodyweight workout may sound ridiculously easy. But that’s only if you haven’t tried the Cindy—the viral CrossFit routine that actor Tom Holland swears by.

I’m a certified personal trainer, and I agree this workout is pretty brutal, but adding these moves to your current training plan is a great way to build the endurance every hiker, climber, or runner needs. Here’s why.

What Exercises Does the ‘Cindy’ Require?

In an interview with Men’s Health UK posted on Instagram recently, the 30-year-old Spider-Man star named the Cindy as his go-to workout when he’s strapped for time but still needs a solid workout. The routine is simple: five pull-ups, ten push-ups, and 15 air squats. “It’s great,” Holland told Men’s Health UK. “Like, you don’t have to think about anything; you just count your rounds.” This routine is meant to build stamina and muscular endurance, according to CrossFit’s website.

The hardest part is repeating that sequence as many times as you can in 20 minutes. Holland said his record is 27 rounds, and that even when he’s feeling “really tired,” he can still eke out 20 rounds by repeating the sequence Every Minute On the Minute. In CrossFit terms, that’s known as an EMOM workout.

Try the Cindy just once, and you’ll understand how impressive Holland’s stats are. For perspective, CrossFit’s website says that for intermediate athletes, a “good score” is eight to ten rounds. Holland is leagues above intermediate.

How CrossFit’s ‘Cindy’ Can Make You a Better Outdoor Athlete

Even if you’re not at Holland’s level, you can still gain a lot from this short-yet-intense routine. For starters, it’s all about performing a bunch of reps in a row, which makes it stellar muscular endurance training. Muscular endurance is your muscles’ ability to work for long periods of time. That carries over well to any outdoor sport, where the big-picture goal is continuous movement with solid form.

It Builds the Upper Body Strength Needed for Climbing, Paddling, and Swimming

The Cindy especially targets the core and upper-body muscles—including the shoulders, chest, arms, back, and abs—through pull-ups and push-ups, making it highly relevant to climbers, paddlers, and swimmers. Even though you’re not using any external load (like dumbbells) to complete those exercises, they still involve moving a significant portion of your bodyweight against gravity (nearly 100 percent of your bodyweight in pull-ups, and up to 75 percent in push-ups), which is no easy feat.

It Targets the Lower Muscle Groups Needed for a Strong Hike

This workout also gives your lower body a great burn. The air squats will be the easiest of the three exercises, provided you don’t have an existing knee or ankle injury. Compared to your upper body, the legs are a much stronger muscle group. So a basic squat without external resistance will feel less taxing than a standard push-up or pull-up.

Because the Cindy centers on busting out as many reps as you can–ten rounds work out to be a total of 150 squats—your legs will still likely feel gassed by the end. That lower-body challenge also makes the Cindy pretty functional for leg-dominant activities like running and hiking.

Another great benefit of the Cindy? It’s a big test of mental fortitude. Your muscles and lungs will likely be screaming at you to stop well before that 20-minute timer goes off. Carrying on anyway, so long as you don’t compromise your form or push into an unsafe intensity, can help sharpen your stamina for whatever outdoor adventure awaits you next.

About the author: Jenny McCoy, CPT, is a certified personal trainer and senior fitness and health journalist based in Colorado. As Outside‘s Moves columnist, she covers the best fitness routines for outdoor athletes. She earned her credentials through the National Academy of Sports Medicine (NASM). In her free time, she lifts weights, plays word games, and goes on outdoor adventures with her daughter, husband, and dog. In her previous story for Outside, she recommended the best standing exercises that can help improve stability in your favorite outdoor sport. You can read it here.

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