Which Is Better: High- or Low-Rep Workouts?

When you’re powering through a strength class coached by Peloton Instructor Adrian Williams, you may not pay much attention to the number of reps you’re doing of each move—you’re just obeying his instructions and trying to survive until the cooldown. But if you’re hitting the gym or trying to program your own workouts, you’ll need to take charge. 

If you’re new to working out or just designing your own workouts, you may be wondering how, exactly, you’re supposed to decide how many reps to do. The truth? It’s both an art and a science, and there’s not a one-size-fits-all answer for every body or workout. 

Deciding on the number of reps for an exercise is all dependent on your personal fitness goals, Adrian says. Yeah, it’s a lot to think about, but we’re here to help. Here’s everything you need to know about rep count, including the perks and downsides of training with high reps vs. low reps, and which to choose depending on your goals.

What to Consider When It Comes to Rep Count

First, let’s review the fundamentals: A rep, short for “repetition,” describes the action of performing an exercise one time (think: a single bicep curl). Reps are usually organized into sets, which are when you complete a certain number of reps in a row. For example, one set could include 10 reps of squats. During a Peloton Gym workout, for instance, you may do 2-4 sets of those 10 squat reps for a total of 20-40 reps.)

As a basic strength training principle, experts recommend that you should feel fatigued—like you can hardly keep going—by the last few reps of a set, according to the National Academy of Sports Medicine (NASM). This is where growth and progress are made, as you’re forcing your body to adapt to handle the challenge. So, if you’re lifting lighter weights, you’ll likely need to do more reps to feel that burn. And if you’re lifting heavier weights, you’ll likely need to do fewer reps before you feel like you need to stop. This is why high-rep workouts are typically done with smaller (or no) weights, and lower-rep workouts are typically done with heavier weights.

What’s a High vs. Low Rep Count? 

According to the strength-endurance continuum model, a low rep count usually falls between 1 and 5 repetitions, a moderate rep range is from 8 to 12, and a high rep count includes sets of 15+ reps. However, these ranges may vary in practice. Ari Adrahtas, ATC, MS, outreach athletic trainer at ATI Physical Therapy, considers 3-8 to be low, and 12-15 to be high. “When I program my strength classes, depending on what the goal is, a high rep count would be 10-14 reps, and a low rep count would be 4-7,” says Adrian. “I cannot stress enough how important the range is for accomplishing what the program sets out to do.” 

Muscular Strength vs. Mass vs. Endurance

Working with higher reps and lighter weights or lower reps with heavier weights will affect your body differently. According to the strength-endurance continuum, low rep counts are best for building muscular strength, moderate rep counts for building muscle mass, and high rep counts for building endurance. 

Muscular strength is “a muscle's ability to produce the most amount of force possible in a single movement,” says Adrahtas. You can think of this as brute strength — the ability to pick up something really heavy or generate a lot of power. For strength you will want to focus on low reps and heavier weight, Adrian says.

Muscular mass is how much space your muscles take up, or how big they are. Hypertrophy is the process of enlarging muscle fibers, typically as a result of resistance training, according to NASM. The key to inducing hypertrophy is increasing training volume, which can be done partially by lifting moderate weight for a moderate number of reps.

Muscular endurance is a muscle's ability to generate a movement consistently over time, Adrahtas says. It’s generally targeted by strength training with higher reps and lighter weight, Adrian adds.

If your goal is to run a marathon or get a new deadlift PR, you might think you need to focus on one of these fitness skills, but that’s not the case. It’s important to vary your training for overall health and wellness, Adrahtas says.

Muscle-Specific Rep Training

“Muscles can respond differently to high and low rep training due to their fiber composition and function,” Adrian says. All your muscles are made up of tiny individual fibers, and those fibers can be grouped into two different types: Type I (slow-twitch) and Type II (fast-twitch).

“Type I muscle fibers, which are slow twitch, respond better to high rep training because they're more resistant to fatigue,” says Adrian.

“Type II, which are fast twitch, respond better to lower reps because they're better suited for explosive/higher intensity workouts,” he explains.

Everyone has both types of muscle fibers in their body, according to NASM, and all the muscles in your body contain a mix of both; however, there are certain muscles that tend to contain more of one type of fiber, depending on the movements they control. For example, your soleus (calf muscles) and upper-back muscles tend to have more Type I fibers, Adrian says, since they’re responsible for walking and maintaining posture. Meanwhile, your quads, hamstrings, and chest typically have a higher proportion of Type II fibers, he says. Then there are hybrid muscles, which contain a more even split (like your deltoids, or shoulder muscles) and benefit from both types of training.

The Pros and Cons of Doing High Reps With Lighter Weights 

Do you feel like your arms are going to fall off after just one song in an Arms & Light Weights class on the bike? That’s proof that, when paired with lots of reps, even light weights can have a big effect. That said, there are both benefits and downsides to performing strength moves with higher reps and lighter weights:

Pro: Muscular Endurance. A high repetition scheme with light loads, defined as 15 or more repetitions per set with loads below 60 percent of 1-repetition maximum (1RM) optimizes muscular endurance improvements, according to a 2021 review in Sports. 

Pro: Muscle Growth. “When you're working higher reps it is all about taxing the muscle for growth. In the industry we call this hypertrophy training, which is a great way to increase the size of a specific muscle group,” Adrian says. Specifically, research has found that a more moderate rep scheme with moderate loads (from 8 to 12 repetitions per set with 60 percent to 80 percent of 1RM optimizes hypertrophic gains, according to a 2021 review in Sports.

Pro: Joint Health. If you’re a beginner or individual with joint issues, or are recovering from an injury, lighter weights and higher rep ranges can be a more gentle option to help you ease into resistance training without added stress on joints.  

Con: Less Strength and Power Development. “Higher rep ranges with lighter weights are less effective for developing maximal strength and power compared to lower rep ranges with heavier weights,” Adrian says.

Con: Risk of Overuse Injuries. Constant repetition of movements over higher reps can increase the risk of overuse injuries, such as tendonitis, Adrahtas says. And this is especially true if you’re not maintaining proper form or taking enough time to recover between workouts. 

Con: Potential Plateau.  If you always do high reps of low weights, you may not be taxing your body enough. The principle of progressive overload explains that, to keep seeing progress in your abilities, you need to keep challenging yourself.

The Pros and Cons of Doing Low Reps With Heavier Weights

You probably already know that lifting heavy weights is hard and good for you—and if you go heavy enough, you probably can’t do too many reps. Performing a strength exercise with lower reps and higher weights can also have several benefits and downsides:

Pro: Strength Gains. Doing lower reps with heavy loads (defined as 1 to 5 repetitions per set with 80 percent to 100 percent of 1RM optimizes strength increases by enhancing neuromuscular adaptations that facilitate force production, according to a 2021 review in Sports.

Pro: Power Development. “Training with lower reps allows for the development of explosive power, crucial for activities like weightlifting or sprinting,” Adrian says. 

Pro: Improved Technique. Lower rep ranges allow for a focus on perfecting technique since each repetition matters more, Adrian says.

Con: Increased Risk of Injury. Using heavier weights increases the potential for acute injuries (such as muscle or ligament tears), Adrahtas says, and it can be more difficult to execute the move with proper form.

Con: Limited Muscle Endurance. “Lower reps primarily target strength and power, neglecting muscle endurance,” Adrian says. This may not be ideal for endurance activities requiring prolonged muscular effort, such as running, hiking, or cycling. 

So, Which Is Better: High Reps or Low Reps?

Variety is the spice of life, and it should be part of your workout routine, too—especially when it comes to choosing rep ranges. It’s imperative to train in both of these manners (high- and low-rep) in order to reduce risk of injury, build diverse strength in the muscles, strengthen joints, and promote overall health, Adrahtas says. That said, if you have a specific fitness goal in mind, you may benefit from dedicating more of your time to either type of training.

High Reps vs. Low Reps For Increasing Strength

If you want to get stronger or set a new PR, consider adding more low-rep, high-weight training to your routine. “A rep range of 1-6 is optimal for building strength in compound movements like squats, deadlifts, and bench presses.”

High Reps vs. Low Reps For Building Muscle Mass

If your main fitness goal is to build more muscle mass (aka hypertrophy), you’ll want to do moderate to high rep ranges with moderate weights, Adrian says. Stick to 8 to 12 repetitions per set with a load 60 percent to 80 percent of your 1RM.

High Reps vs. Low Reps For Endurance Sports

This one may be self-explanatory, but if endurance is your goal—either to play through a whole soccer game, bike a 50-miler, or finish a half marathon—high-rep training should occupy a significant chunk of your strength routine.

High Reps vs. Low Reps For Power and Sports Performance

“Low-rep training emphasizes explosive movements and maximal force production, making it ideal for developing power and speed,” Adrian says. These skills are crucial for anyone involved in sports like soccer, basketball, or pickleball that require explosive movements, such as sprinting, jumping, or throwing.

How to Understand Your Fitness Goals and Adjust Your Workouts Accordingly

If you have a specific fitness goal you’re working towards, you can tailor your rep ranges to build strength, muscle mass, or endurance—but everyone can benefit from having both types of training in their routine. “I like to stay well rounded in my training and do both, but I absolutely love lower rep training because of the purpose it serves for my personal goals,” says Adrian. “A lot of folks are intimidated to lift heavier because they have never had the opportunity to or they haven't been educated on its benefits. Heavy lifting requires the programming to be much slower and more intentional,” he explains. “The messages that I have received from Peloton Members who have told me their riding, running, or rowing has become more efficient is why I continue to recommend individuals include strength training in their exercise routine.”

This content is for informational and educational purposes only and does not constitute individualized advice. It is not intended to replace professional medical evaluation, diagnosis, or treatment. Seek the advice of your physician for questions you may have regarding your health or a medical condition. If you are having a medical emergency, call your physician or 911 immediately.