You might be aware that it’s not ideal to rest on consecutive days, but how detrimental is it truly to perform squats followed by cycling, or have intense HIIT workouts every day? If you’re not repeating the same workout every day, is it acceptable to target the same muscle groups on consecutive days?

In general, it is acceptable to engage the same muscle groups on consecutive days, as long as you avoid reaching muscle failure during either of those days, affirms Lindsay Ogden, a certified personal trainer and nutrition coach at Life Time Athletic in Chanhassen, Minnesota. By “reaching muscle failure,” she means reaching a point where you are physically unable to perform the exercise due to muscle exhaustion. Although this is commonly experienced during strength training (when you can’t complete another repetition), your legs likely experience a similar sensation after a long run or an intense HIIT class.

Interestingly, there are advantages to working the same muscle group on consecutive days if you follow the correct approach: “It can promote recovery and prolong the duration of protein synthesis, leading to an extended period of muscle building,” explains Ogden. The concept involves targeting a muscle group intensely one day with heavier weights and fewer repetitions (around three to eight reps), and then targeting the same muscle group the following day with lighter weights and more repetitions (around eight to 12 reps).

“The objective is to activate the cells that stimulate muscle hypertrophy (commonly known as muscle growth) and supply nutrients to the muscles,” adds Ogden. However, going to the gym on consecutive days isn’t the only way to reap these muscle-building benefits. “Adequate sleep, stress management, and proper nutrition also contribute to this process,” she explains.

What You Should Consider About Working the Same Muscles Consecutively

If you want a detailed overview, here is what you should keep in mind when it comes to performing the same workouts and targeting the same muscle groups on consecutive days, depending on the type of routine.

Strength Training

The most crucial aspect of strength training? Recovery. Building strong muscles requires time, and not just the time spent at the gym. “You don’t improve during your strength workouts — you improve in between them,” emphasizes Neal Pire, C.S.C.S., an exercise physiologist located in Englewood, New Jersey.

During training, muscles endure stress; then, over a span of a day or two, they recover and rebuild themselves, becoming stronger than before.

Many factors influence the speed at which your muscle fibers recuperate after engaging in resistance exercises (that is, your level of physical fitness, the amount of weight you are lifting, and the number of repetitions you perform). However, for the typical individual, it is advisable to target the same muscle group no more than twice per week, ensuring a minimum of 48 hours elapse between each session, as proposed by Pire. Therefore, it is best to avoid engaging in strength training for the same muscle group on consecutive days.

Instead, attempt striking larger muscle groups (such as the pectorals, dorsal, deltoids, quadriceps, and hamstrings) with heavier weights earlier in the week, suggests Jen Hoehl, an exercise physiologist based in New York City. Then later in the week, when you’re more likely to feel fatigued, work on smaller muscle groups (such as the forearms and gastrocnemius) with lighter weights and higher repetitions. Doing this allows you to be refreshed when you’re exerting maximum effort and lifting heavy, while building stamina later.

Cardio

Engaging in cardiovascular exercise — whether it’s jogging or biking — on consecutive days usually isn’t that risky, as long as you’re not going from zero to sixty with your training intensity and frequency, Jacqueline Crockford, an exercise physiologist at the American Council on Exercise, previously informed Shape. Gradually increase your training and pay attention to your body to avoid any repetitive strain injuries and prevent hitting a plateau.

But is it detrimental to lift those three-pound dumbbells in cycling class every day? Not truly — since those cycle and barre class exercises aren’t precisely classified as strength training. “Spinning and the light upper-body dumbbells some classes call for don’t provide sufficient resistance to cause muscle breakdown — the high-repetition, low-weight movements are intended to introduce variety and elevate heart rate,” says Hoehl. So feel free to cycle and lift weights daily — but if you desire genuinely strong biceps, detach from those pedals and attempt barbell weight training at least twice a week.

HIIT Training

“High-intensity, total-body workouts (like burpees) don’t exert the same muscular strain as traditional strength workouts, so it’s permissible to do them on consecutive days,” says Pire. However, “if you’re performing compound or multi-joint movements, you’re engaging multiple (muscle) groups simultaneously — which can also be arduous and necessitate more recovery,” says Ogden.

That’s why, if you engage in excessive HIIT training, you may encounter symptoms of overtraining syndrome. To prevent that, alternate between HIIT days and strength days — with low-intensity active recovery days, of course. “A combination of HIIT and heavyweight lifting will assist you in achieving a lean appearance,” adds Hoehl. (See: Here’s What a Perfectly Balanced Weekly Workout Schedule Looks Like)

Abs Workouts

Ab workout is generally focused on conditioning or endurance rather than strength, so feel free to add it to your workouts on a daily basis,” says Pire. Just make sure to vary your exercises: “Your core is always responsible for keeping you stable, so recovery of the abdominal muscles happens quickly,” says Hoehl. Abs quickly adapt to stress, so make sure to do a different ab exercise every day, he adds.