This article is brought to you by ISSA (International Sports Sciences Association)
There just isn’t a simple, short answer to this question because of all the complicating factors: type of workout, fitness level, fitness goals, weight goals, and more. 
As you plan training sessions for clients, or for your own fitness goals, consider individual goals, needs, and abilities. A competitive bodybuilder’s workouts will be much longer than a senior just getting into fitness. Personalizing workouts, not just by type and intensity but also by duration, is important for helping your clients hit their fitness goal. 
For Fitness Beginners – Ease into Working Out
Beginners should start with shorter workout sessions than anyone more experienced in fitness. Going too long right away can lead to injury. It can also be discouraging and keep your clients out of the gym. Start small with shorter workouts, even just 20 minutes, to build their fitness, teach them gym skills, and work on form. 
Any longer workouts for beginners should be of lower intensity. For instance, a 40-minute walk on the treadmill is reasonable, even for a newbie. These longer workouts, even if they aren’t very intense, help them build endurance. 
It’s important to encourage beginners to hit the gym. They need to be prepared, though. Make sure your clients don’t make these beginner mistakes that can stall workouts or even cause injuries. 
How Long Should Your Workout Last for Weight Loss? 
For many of your clients, the goal of working out is to lose weight or to maintain a healthy weight. While shorter, HIIT-type workouts have become trendy and are promoted as big calorie burners, the truth is that weight loss requires longer periods of exercise. 
Research shows that 150 to 250 minutes of moderate-intensity exercise per week prevents weight gain and supports modest weight loss. More than 250 minutes per week supports more significant weight loss. If you aim for 250 minutes then, a simple breakdown is five 50-minute workouts per week. (1)
Of course, a set schedule of 50 minutes five times a week is not ideal for everyone. There are benefits to varying workouts too. For instance, one shorter HIIT workout per week can really rev up the metabolism and aid weight loss. Here’s a reasonable schedule for a week of workouts for anyone looking to lose weight: 
  • One short, hard workout, like a HIIT workout, for 20 to 30 minutes. These intense workouts do not need to be long to be effective. 
  • Two easy, 30 or 45-minute workouts per week. Consider these to be active recovery days. The workouts should be low-intensity, for instance, a walk or yoga. 
  • Three moderate-intensity workouts of longer duration, 45 to 90 minutes. Mix up strength training and cardio for these longer workouts. They should get your heart rate going but not be as intense as a HIIT workout. 
Do you have a client struggling to lose weight? It may not be the workouts that are to blame. Diet is an even bigger factor in weight loss. Check out these nine weight loss myths that may be keeping your clients from reaching their goals. 
Workout Lengths for Different Types of Exercise
Everyone, despite ability level or goals, needs to be doing some amount of cardio and strength training. These two main types of exercise build muscle, burn fat, improve stability and balance, and improve cardiovascular fitness and health. They are very different, though, and that means you may spend more time on one than the other. 
How Long Should Your Workout Last for Cardio? 
Cardio workouts can vary significantly in duration depending on the day, the type of workout, and the individual. One day, you may do a 20-minute HIIT session and the next a long, slow 60-minute run. The most important thing about cardio is that you do it and for at least 10 minutes at a time. 
The Centers for Disease Control and Prevention recommends 150 minutes of moderate-intensity exercise and 75 minutes of vigorous physical activity per week at a minimum. (2) For health benefits, you can split this up any way you want. 
Of course, for specific training or weight goals, you may need to develop a more carefully thought out routine. For instance, if you have a client training for a marathon, they will need more long-duration cardio than your client who just wants to get healthier. 
What About Strength Training? 
As with any workout, the duration of a strength or resistance training workout depends on multiple factors. A good general rule for strength training depends on the frequency of sessions: 
  • If you’re doing just two strength training workouts per week, they should last between 45 and 90 minutes. The exact duration depends on individual factors, like experience, fitness, and goals. 
  • For more frequent sessions, four to six per week, each workout can be much shorter, even just 30 minutes. 
Another factor to consider is progression. A client just starting out with strength training will make quick gains with minimal time in the gym. As they get fitter and stronger, they need to progress. This means increasing weights but also duration. Their weight training sessions may need to get a little longer over time to achieve muscle growth. 
For clients pressed for time, new research says a short, intense strength workout can be effective for building muscle mass. (3) The idea is to do one intense set rather than the more traditional three sets of exercises. For this to work, that one set has to be so tough that you couldn’t do another one even if you wanted to. 
Only try this kind of workout with clients who have experience lifting and good form. Also, make sure they realize that it isn’t ideal. The study shows you can make gains this way, but it is not better than a longer workout. Use this short session only when you must. 
Can You Train for Too Long? 
Yes, you definitely can. Most of your clients are not at risk for this. For most people, just getting into the gym for a regular workout routine is the struggle. However, you may run into clients who push it too hard and for too long, risking burnout and injury. 
An injury is the most serious consequence of working out for too long, but there are other concerns, especially with strength and conditioning workouts: 
  • The quality of a workout decreases when you over do it. Excessive fatigue means you can’t do exercises with maximum effort or power, or good technique, and you won’t get the full benefits. 
  • An extended workout can trigger the breakdown of muscles for energy, the opposite of what you’re trying to achieve. 
  • Muscle recovery becomes more difficult when you workout excessively. The repair process simply can’t keep up with the damage you’re doing to muscle tissue. 
  • This kind of training isn’t sustainable. You’ll hit an overtraining plateau, which causes persistent fatigue, an elevated resting heart rate, and loss of muscle strength. 
Unless you are working toward an intense, short-term goal, like a fitness competition, with expert guidance, working out for two hours or more a day is not a good idea. It’s not sustainable and can actually derail your goals. 
There are a lot of specific answers to this question of workout duration, but one important general answer: as long as you can or want to, without overdoing it. Most people are not at risk for working out too much or for too long. Some people may be at risk of overtraining, but most clients you have will be looking for shorter workouts that are effective. 
Encourage your clients to work out when they can and for reasonable amounts of time. Unless they have a difficult fitness goal, like a fitness competition or athletic event, workout length isn’t all that important. Just get them in the gym regularly. 
(1) Donnelly, J., Blair, S., Jakicic, J., Manore, M., Rankin, J., & Smith, B. (2009). Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Medicine & Science in Sports & Exercise, 41(2), 459–471. https://doi.org/10.1249/mss.0b013e3181949333 
(2) Centers for Disease Control and Prevention. (2021, July 29). Physical activity recommendations for different age groups. Centers for Disease Control and Prevention. Retrieved November 16, 2022, from https://www.cdc.gov/physicalactivity/basics/age-chart.html 
(3) SCHOENFELD, B. J., CONTRERAS, B., KRIEGER, J., GRGIC, DELCASTILLO, K., BELLIARD, R., & ALTO, A. (2019). Resistance training volume enhances muscle hypertrophy but not strength in trained men. Medicine & Science in Sports & Exercise, 51(1), 94–103. https://doi.org/10.1249/mss.0000000000001764 
Blog Category: