How to exercise for muscular strength, endurance and size
In addition to getting at least 30 minutes of aerobic activity most days of the week, the American Heart Association recommends doing full-body resistance training two to three days per week to strengthen muscles, bones and connective tissue. Resistance training also lowers risk of injury and increases metabolism, which makes it easier to maintain a healthy weight.
Certified strength and conditioning specialist Joshua Laudig, NSCA-CPT, fitness coordinator at the Texas A&M Coastal Bend Health Education Center and Texas A&M Healthy South Texas, says it’s not enough to just lift weights or do some pushups a few days a week to meet the recommendations above.
“Always have a goal in mind when setting up your workout plan,” Laudig said. “With resistance training, there are essentially three different outcomes you can aim for: muscular strength, endurance and hypertrophy (or increase in size). Ideally, your exercise program will target all three.”
When it comes to exercise, consistency is key.
“The most important thing is to stay consistent over time,” Laudig said. “Keeping a routine and staying consistent with your workouts goes a long way in helping you create healthy habits. Over time, exercise will become part of your normal routine.”
If you’re doing fewer than four resistance training sessions per week, Laudig recommends focusing on full-body training. This allows you to work every muscle group during one session, while still giving your body time to recover between workouts.
To maximize your resistance training sessions, do them before cardio, or do cardio on a separate day to avoid over-fatiguing your muscles and sacrificing good form.
Choose the right weight
For each of the repetition ranges below, choose a weight that makes the last rep difficult, but not impossible.
“If you can easily get all 15 reps, you can most likely increase the weight. But if you’re struggling and reaching muscular fatigue, you may need to lighten the load,” Laudig said. “You want to ‘leave one in the tank,’ as we say. Meaning, you could accomplish just one extra rep at the end.”
To improve strength, focus on big movements that engage multiple joints and muscle groups to overcome the resistance. Some examples of multi-joint exercises are squats, lunges, hip hinges, pushups, rows and shoulder press. Choose eight to 10 different exercises and perform three to five sets of one to five repetitions of each.
“Training for strength is exactly how it sounds: You’re trying to lift as much weight at once as you (safely) can, so aim for high weight and low reps,” Laudig said.
Muscular endurance is how long you can move weight around. In this range, you’re aiming for more reps, so your load should be lighter.
Movements that increase endurance include multi-joint movements as well as isolated, or single-joint, movements.
“Single-joint movements target the ‘pretty’ muscles—like biceps, shoulders and ‘six-pack’ abs—so we call this ‘accessory’ work,” Laudig said. “Do accessory work after multi-joint movements.”
Examples of single-joint movements include bicep curls, shoulder raises, triceps extensions and abdominal work. These exercises engage just one muscle at a time.
For endurance, complete two to four sets of 10 to 15 repetitions.
Increase in muscle size is called hypertrophy. As you put repeated stress on your muscles in just the right amount, the body adapts by building larger, stronger muscles to overcome the bigger load.
To achieve hypertrophy, choose the same movements you would do for endurance, but decrease the number of reps slightly to accommodate a heavier weight. Do three to four sets of eight to 12 repetitions.
Now put it all together
Although focusing on a certain rep range will help you reach specific outcomes, Laudig says it’s always important to spend time in each of these phases to achieve a better overall fitness level. Switching from endurance to hypertrophy to strength training will help build overall fitness while also giving your body the benefit of different stimuli. Changing up your focus for a few weeks at a time will give your body a new stimulus to overcome while also keeping you engaged and making progress toward your goals.