The Essential Skill You Start Losing in Your 20s—and Runners Often Neglect to Train

Ann Chisholm, owner and coach at Tropos Fitness Club in Victoria, British Columbia, stands before a crowd of about 20 women huddling in a circle under an outdoor tent, eager to learn about strength training despite the rainy weather.“What are three common weaknesses in endurance athletes I see in the gym?” she asks them.The group shouts out guesses. The first two are easy. Glutes! Adductors!—Chisholm agrees.What’s the third one? Hip flexors? They’re up there, but there is something more important, Chisholm says.This is the last session on the last day of FeistyFest, a three-day movement and educational festival for women held in September in Breinigsville, Pennsylvania, and none of the previous groups guessed the third one correctly, Chisholm says, before revealing the answer: “Power explosiveness!”You can think of your explosive power as those first couple of seconds of your movement, the initial burst, Chisholm says. You’re recruiting fast-twitch muscle fibers, which quickly contract and generate high force, and activating your nervous system, which fires signals to your muscles at a high speed to help you coordinate complex movements.“Injuries don’t happen when you’re just simply running forward often,” Chisholm says. When she sees them happen most? While moving laterally—“when you have to move quickly or in a different direction.” And that’s where explosive power comes in to help.When you run, your body absorbs two to three times your body weight, which puts a lot of pressure on your joints and ligaments. Explosive power helps you control those forces safely and efficiently, while also improving speed, stride efficiency, and joint resilience.Let’s start with the bad news: a 47-year Swedish study from 2025 published in the Journal of Cachexia, Sarcopenia and Muscle concluded that explosive power peaks in women at 19 and in men at 27. That’s when your body starts losing its first line of defense against sudden physical stressors, and you become more injury-prone.The good news? “We can train that, so your body is prepared to absorb the impact,” Chisholm says.How to Train Explosive PowerExplosive power complements strength training, building on it. While strength training is all about the maximum amount of force a muscle can generate, explosive power helps you apply that power as quickly as possible.Especially if you’re new to training your explosive power, adding one or two movements to your strength training session to start and slowly building up from there is the way to go, Chisholm says. “It could lead to injury if you do too much too fast, versus the actual goal that we want from it: to help with injury prevention,” she explains. “It’s really demanding, it’s hard on our body, and so we want to train it in lower reps.”Besides how much, when you train explosive power also matters—you want to prime your body with explosive work before you get into strength. “When we want to train and get better at the explosive and power work, we need that fresh nervous system,” Chisholm says.Chisholm is an ultrarunner, but she also used to play basketball, where agility and explosive power are essential and require training. Blending these two experiences, as a trainer, she programs athletic-style workouts that always include explosive power-focused moves in strength sessions. She starts with three Rs.Readiness: This is your warmup. You prepare your body for the session and activate muscles you’re going to use in the workout. Reactive: This is the explosive power work—and the most demanding on the body—so you want to complete that work before you do strength training.Resistance: This is the bulk of the workout, the strength work. This is where you, as a runner, will focus on key weak areas: hip flexors, adductors, and glutes. During all workouts, you want to train lateral movement—whether that is in the power and explosive section (for example, a lateral bound) or in the resistance work (for example, Copenhagen plank or lateral lunges).Here are some examples of moves from Chisholm that train explosive power. She models many of them on her YouTube if you need a visual for any of the exercises.Dynamic pogo hops: Jump up and downBox squat to vertical jump: Slowly descend on a box or a bench as if you’re doing a squat, and jump up after you touch downHop hop land: Hop twice in a row, then land softly on one leg and hold your balanceReversed lunge to single-leg hop: Step one foot back into a lunge, then push off your front foot and hop up, landing on that same footLateral Heidens: Hop sideways from one foot to the other, landing softly and balancing before you hop backTriple broad jump: Jump forward three times as far as you canSkater squat: Stand on one leg, bend that knee, and lower your other knee toward the floor behind you. Rise back up.Below is a sample workout for a runner new to strength training.Warm up:5 min bike or walk Open books | 5 reps per sideMonster walks | 15 reps per side Band pull-aparts | 15 reps per sideSkips | 30-40 seconds Strength:2 sets:A1. Lateral Heidens | 10 reps per sideA2. Hip flexor leg lifts | 10 reps per sideA3. Hop hop land | 5 reps per side3 sets:B1. Split squat | 8 reps per sideB2. DB bench press | 8-10 reps per sideB3. Side plank | 30 sec per side3 sets:C1. Single-leg RDL | 8 reps per sideC2. Lateral lunge | 8-10 reps per side2-3 sets:D1. Half kneel overhead press | 8-10 reps per sideD2. Bent-over row | 8-10 reps per sideD3. Weighted dead bug | 8-10 reps per sideHow to Incorporate Explosive Power Training Into Your Running ScheduleWhen you look at your week, think of each day as high, medium, or low, Chisholm says.For most runners, high days are greater time/volume but also output, and include:long runspeed/threshold/capacity one bigger strength day any day where two workouts are happeningMedium days include:a second or secondary and potential third strength day easy runsLow days include:rest days optional short easy runsmobility/yogaYou don’t want to stack all your high days together, and you don’t want a strength training session to affect your long run. Because a strength training session is a high-to-medium effort, you want it to be followed by a low-effort day. With that in mind, here’s how your week could look:Sunday: long run (HIGH) Monday: strength (MEDIUM)Tuesday: rest (LOW)Wednesday: speed (HIGH) Thursday: easy run (MEDIUM)Friday: strength (HIGH)Saturday: rest or mobility/yoga (LOW)Pavlína Černá, an RRCA-certified run coach and cycling enthusiast, has been with Runner’s World, Bicycling, and Popular Mechanics since August 2021. When she doesn’t edit, she writes; when she doesn’t write, she reads or translates. In whatever time she has left, you can find her outside running, riding, or roller-skating to the beat of one of the many audiobooks on her TBL list.