What is the best interval?
If you’re not familiar with interval training, it is where you perform an activity (commonly cardio) for a certain amount of time and then switch difficulty. For example you could walk on a treadmill at level 4 for 1 minute, switch to level 7 for one minute, and then repeat this for the duration of your workout.
As for what the best interval is, that depends on two things, your current fitness level and your goals. Therefore, the answer is different for everyone and since your fitness level changes over time, the interval you use should change as well. Actually, it is beneficial to use a variety of intervals during different workouts to improve multiple aspects of fitness and help prevent plateaus.
Unfortunately, I am not able to give you a specific answer since there are so many unknown variables, but I do have some advice to help you figure out how to narrow in on your interval(s). On a basic 2 interval plan, the more difficult interval should be fairly challenging and the second interval should be reduced enough that you can recover a decent amount before repeating the more difficult one.
As your fitness improves, you can increase the difficulty of the more difficult interval, the easier interval, or both. The important thing is the overall workout remains challenging. If the interval combination is too easy or familiar, your results will not be as good and if it is too hard, you will not recover enough and your body will start wearing down, leading to overtraining.
As for your goals, if you are more interested in endurance, you should focus on increasing the length of the difficult interval and/or shorten the length of the easier (recovery) interval. If you are more concerned with short duration (strength/power) activities, you could focus more on increasing the intensity of the more difficult interval and possibly decreasing the length of the recovery interval to help train repeated power production.
These are just some common examples, but intervals can be modified in many different ways. You could also have three or more different interval difficulties in the same workout and some machines have programs where every interval is a different intensity throughout the workout. Between changing the difficulties and/or lengths of intervals, there are essentially unlimited options to choose from.
As long as the intervals match your ability level and goals, many different intervals can be equally effective. Just be sure to continue increasing the overall difficulty as your fitness level increases. In addition, with intervals or any workout for that matter, the more you repeat the same workout the less effective it becomes. Therefore, there really is no such thing as a best interval, because intervals should change regularly.
By Ross Harrison
VFT Fitness Expert
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