This morning, I lead one of my clients through a brand new workout. She has been making great progress and it was time to step it up. She explained that she didn’t feel as successful during this workout as she did in previous workouts. This response was to be expected. Your body must respond and adapt to new stimuli.

The General Adaptation Syndrome (GAS) was developed by Hans Selye in 1956. This concept describes the three-phase response to stress. Because exercise is stressful on the body -in a good way- the GAS can be applied to resistance training.

The first phase of the GAS is the alarm phase. This occurs when you increase the intensity of your workout. Whether you increase the amount of weight you lift, the amount of sets you do, or the amount of exercises you do, your body becomes stressed. During the alarm phase, you will likely be sore, stiff and fatigued and you will experience a temporary drop in performance. This is your body’s normal reaction. When you first learned to ride a bike, you weren’t perfect on that first attempt. Don’t expect perfection when learning new skills.

The second phase of the GAS is the resistance phase. Your body adapts to the stimulus and returns to normal functioning. Your brain makes more connections to your muscles which leads to improved performance. In this phase, you must continue to vary your workouts and gradually increase intensity.

If you continue to increase intensity without adequate time to adapt, you reach the third phase of the GAS: exhaustion. Some of the same symptoms experienced during the alarm phase reappear during this phase. Other stresses such as insufficient sleep, poor diet, and job-related stress can contribute to overall stress and can lead to the exhaustion stage. Planning easier workouts or recovery periods will help you avoid this phase.

It’s important to increase the intensity of your resistance workouts in order to make progress and see results. And it’s just as important to give your body rest, especially during stressful times. Don’t overtrain. Train with purpose and consistency.