Writing a great workout requires careful consideration of many factors. While all of them are important, intensity and duration play a great role in our consistency of exercise, and therefore our results. Intensity can be described as how hard you’re working, and duration is the amount of time spent working. It’s important to be mindful of these factors and acknowledge that they should change from workout to workout. 

According to the American College of Sports Medicine, all healthy adults should participate in moderate intensity aerobic physical activity for a minimum of thirty minutes on five days per week. Another way to hit the recommended amount of exercise is to participate in vigorous intensity aerobic activity for a minimum of twenty minutes on three days per week. Notice here how as intensity increases from moderate to vigorous, duration decreases from thirty minutes five days per week to twenty minutes three days per week. These two variables have an inverse relationship when it comes to exercise and it’s important we keep this in mind. 

We often think that the higher the intensity and the longer the workout, the better, but this simply isn’t true. Both high intensity and moderate intensity workouts have many benefits and each have their place in a well-constructed program. High intensity workouts are a great option when you are short on time, working near your maximum limit, or are looking to work on your heart rate recovery, or amount of time it takes to get back to a resting heart rate after a bout of hard work. Keep in mind that the higher the intensity of the workout, the longer it’s going to take your body to recover. It’s not recommended to do high intensity workouts every single day without resting in between. 

We are able to work at a moderate intensity for a longer period of time, and this is where it is possible to increase the duration of your session. For example, let’s say you’re going for a run. If you go out at a jogging pace, you’ll be able to run much farther than if you start off at a sprinting pace. The same is true for strength training as the closer you get to your one-rep maximum for a specific exercise, the fewer reps you’ll be able to do. It’s important we program our workouts in this way because if we push the duration too long when intensity is high, we are putting ourselves at a higher risk for injury. 

It is possible to do a high intensity workout that lasts a long time and you are more than capable, but it can become very challenging to repeat this pace for every workout. If you’re having trouble sticking to your workout program, check in and see if your workouts are both high in intensity and duration. If they are, consider changing some of them to be high intensity and short duration or moderate intensity and longer duration. This will help with your consistency from workout to workout and will help you complete your program and make exercise a habit you actually enjoy.