The optimal duration of strength training is crucial for achieving maximum results in muscle building and strength development. We’ll explain, based on scientific evidence, how long your strength training sessions should last and which factors play a key role in this.
The Scientifically Proven Ideal Workout Duration
The ideal duration for strength training is between 45 and 60 minutes per session. After about 45 minutes, cortisol levels rise sharply and testosterone levels drop, creating an environment in the body that promotes muscle breakdown. These hormonal changes can significantly reduce the effectiveness of your workout.
However, studies by Schoenfeld et al. show that even training sessions lasting just 13 minutes can lead to significant improvements in strength and strength endurance, provided the training is performed regularly. The optimal balance between training effectiveness and hormonal stress, however, lies in the range of 45–60 minutes.
It's important to know that hormone levels return to normal about 60–90 minutes after a workout, so occasional longer workouts aren't necessarily harmful.
Workout Duration by Experience Level
Beginners (0–6 months of training experience)
For beginners, we recommend a workout duration of 30–45 minutes per session. This amount of time is more than enough to work all the major muscle groups with 6–8 basic exercises. Longer sessions often lead to a loss of concentration and an increased risk of injury for beginners.
A typical workout for beginners should follow this structure: a 5- to 10-minute warm-up, 25 to 30 minutes of strength training with 2 to 3 sets per exercise, and a 5- to 10-minute cool-down. This structure ensures optimal training results without overexertion.
Rest periods between sets should be 60–90 seconds, which, with 12–15 working sets, results in a total workout duration of about 35–40 minutes.
Advanced (6–24 months of training experience)
Advanced athletes can increase their workout duration to 45–60 minutes. As training experience increases, the training volume increases through more exercises, sets, and longer rest periods between heavy sets.
An advanced workout can include 8–12 different exercises, with 3–4 sets per exercise. With rest periods of 90–120 seconds between sets, this results in a natural workout duration of 50–65 minutes.
Split training allows advanced athletes to train more intensively, since only specific muscle groups are worked during each session. This justifies longer training sessions within the optimal time window.
Experts (with more than 24 months of training experience)
Experienced strength trainers can perform workouts lasting 60–75 minutes, but should not exceed the 90-minute limit. During high-intensity training with heavy weights, longer rest periods of 2–3 minutes between sets are necessary.
Experts often use periodized training plans with varying training intensities. On heavy training days with low rep counts, the duration of the workout may increase due to longer rest periods, while on volume days with higher rep counts, shorter, more intense sessions are performed.
Hormonal Effects of Training Duration
Cortisol and Testosterone Balance
After about an hour of strength training, testosterone levels begin to drop and cortisol levels begin to rise. This hormonal shift is extremely detrimental to muscle growth, as cortisol promotes catabolic (muscle-breaking-down) processes, while testosterone has anabolic (muscle-building) effects.
The cortisol-to-testosterone ratio is an important indicator of training load. A persistently elevated cortisol-to-testosterone ratio can lead to overtraining, reduced recovery, and stagnant progress.
Increased cortisol production can lead to a significant reduction in free testosterone and cause a short-term "overreaching effect"—that is, short-term physical overload due to increased training intensity.
Optimizing the Hormonal Response
To minimize the hormonal strain, you should plan your workouts in a structured way. Start with the heaviest, most complex exercises when your strength and concentration are at their peak. Toward the end of the session, you can perform lighter isolation exercises .
The training intensity should be distributed evenly throughout the entire session. Starting sets that are too intense can lead to early fatigue, while starting sets that are too easy do not make optimal use of the available training time.
Factors That Influence Optimal Training Duration
Training Frequency and Volume
The frequency of your workouts has a significant impact on the optimal duration. If you work out two to three times a week, you can do 45- to 60-minute sessions to target different muscle groups each time.
When training more frequently—4–6 sessions per week—shorter sessions of 30–45 minutes are often more effective, as the total training load is spread out over the week, allowing for better recovery.
Your weekly training volume should remain consistent, regardless of whether you spread it out over a few long sessions or many short ones.
Training Goals and Methods
Different training goals require different training durations:
Maximal strength training: 60–75 minutes are often necessary, as longer rest periods are required between heavy sets. Recovery of the central nervous system takes 3–5 minutes when lifting loads exceeding 90% of one’s maximum strength.
Hypertrophy training: 45–60 minutes is ideal, as it involves moderate loads with rest periods of 90–120 seconds. This time frame allows for a high training volume while maximizing the hormonal response.
Strength endurance training:30–45 minutes is sufficient, since short rest periods of 30–60 seconds are used and the intensity is lower.
Individual Regenerative Capacity
Your individual ability to recover has a significant impact on the optimal duration of your workouts. Factors such as age, sleep quality, stress, diet, and genetic predisposition determine how well you can handle longer workouts.
Older athletes often need longer rest periods and should adjust the duration of their workouts accordingly. Starting at age 40, it is recommended to reduce the duration to 45–50 minutes per session.
Work-related or personal stress can further increase cortisol production, making shorter, intense workouts more effective than long, moderate sessions.
Structuring the Optimal Training Session
Warm-up (5–10 minutes)
A proper warm-up is essential and should not be included in the actual workout time. A 5- to 10-minute general and specific warm-up optimally prepares your body and mind for the workout.
The warm-up should be progressive: 2–3 minutes of light movement to raise body temperature, followed by dynamic movements and specific warm-up sets for the first exercises.
Main Part of the Workout (30–50 minutes)
The main part of the session should be structured as follows: Start with heavy, complex exercises when neuromuscular fatigue is still low. Isolation exercises and equipment can be used toward the end of the session.
An effective workout sequence begins with compound exercises such as squats, deadlifts, or bench presses, followed by supporting exercises and concluding with isolation exercises.
Cool-Down Phase (5–10 minutes)
The cool-down phase promotes recovery and should include light exercise and stretching. This time investment pays off in the form of better recovery and a reduced risk of injury.
Common Mistakes Regarding Workout Duration
Workouts that are too long
Many athletes believe that longer workouts automatically lead to better results. The typical workout duration ranges from 30 to 90 minutes or more, but longer sessions are often counterproductive.
Workouts lasting more than 90 minutes often lead to a loss of concentration, an increased risk of injury, and suboptimal training quality. The final exercises are often just "gone through the motions" rather than performed at full intensity.
Intense phases that are too short
On the other hand, training sessions that are too short—less than 30 minutes—can limit training volume and make it harder to achieve long-term adaptations. While short, intense sessions certainly have their place, they shouldn't be the norm.
Ignoring Individual Factors
Following training plans without adapting them to your personal circumstances often leads to suboptimal results. Factors such as available time, recovery capacity, and training experience must be taken into account.
Frequently Asked Questions (FAQ)
Is 45 minutes of strength training enough?
Yes, 45 minutes is more than enough for most athletes. This duration allows for an effective workout of all major muscle groups without negatively affecting hormonal balance.
Can I work out briefly every day instead of working out for longer periods less often?
A short daily workout (20–30 minutes) can be effective, but it requires careful planning of which muscle groups to target and adequate recovery time. For beginners, 3–4 longer sessions per week are usually more practical.
What happens during training sessions that last longer than 90 minutes?
Very long training sessions can lead to increased cortisol release, decreased concentration, and a higher risk of injury. The quality of training usually suffers significantly.
Should breaks between sets be included in the workout time?
Yes, rest periods are part of the training time. They are essential for recovery and for maintaining training intensity, and should be chosen based on the training goal.
How can I tell if my workout duration is optimal?
The best indicators are: consistent increases in strength, good recovery between sessions, high motivation during training, and the absence of symptoms of overtraining.
Do I need to adjust the duration of my workouts as I get older?
Yes, recovery time increases with age. Shorter, intense workouts of 45–50 minutes are often more effective than longer sessions with decreasing intensity.