Optimal Training Duration: How Long Should You Spend In The Gym?

As athletes, we rack up hours and hours of training time in search for improvement.

There are all kinds of theories as to how long you should spend on each workout, with claims that going over or under a gold standard of duration could have a detrimental effect on fitness gains.

A lot of studies have looked into the effects of different durations of various exercise intensities and here, Built for Athletes looks at what the fitness community views as the optimal training duration.

Duration & Hormone Balance In Strength Training

When it comes to the duration of strength workouts, the key debate centres around cortisol levels.

Cortisol is a catabolic hormone released when you exercise, and there is an association between a spike in cortisol and a decrease in testosterone, an anabolic hormone responsible for muscle growth and repair.

Studies have shown that this shift of hormone levels tends to take place between 45 and 60 minutes of intense weight training. Those findings have led to a wide perception that training for longer than an hour is actually counterproductive.

So while there have been many successful athletes who have favoured long sessions - Arnold Schwarzenegger, for example, was known to regularly spend around 2 hours in the gym - a duration of around an hour is likely where you’ll see optimal results.

Aerobic Exercise

When it comes to high-intensity aerobic exercise, there is less of a precise consensus on the training benefits that are gained from each duration.

In general, around 20-40 minutes of total volume for interval training at 80-95 per cent effort is considered the correct dosage, although elite athletes are known to go up to 50 or even 60 minutes.

Experienced runners, cyclists or swimmers tend to have a good idea of how their body reacts to various durations and many coaches will tend to follow the principle of progressive overload by building up the total volume gradually.

Markers of overtraining such as heart rate variability or general feelings of fatigue can be used to assess how well the body is coping with training.