When you workout your body uses stored and circulating energy like your car uses fuel to move. You need gas in your car and glucose in your body. Gas only lasts so long in your car and glucose only lasts so long in your body. All energy/fuel gets used up and needs to be replenished/refueled. Let’s talk about your body energy.
To keep it simple, let’s say there are two main energy systems in your body, anaerobic and aerobic. Aerobic is “with oxygen” and anaerobic is “without oxygen”. The two energy systems fuel exercise, but differently. Aerobic exercise means that oxygen is needed for fuel, for performance. Not necessarily the oxygen you breathe in the air, but the cells need to be able to utilize the oxygen in your body for fuel. These activities are typically greater than 2-minutes and are performed at a low-moderate intensity for a prolonged period of time. Examples include, leisure bike ride, run/walk for 3 or more miles, hiking, etc. Aerobic training improves heart health, aerobic capacity, blood pressure, cholesterol, and mood, yet limits the capacity for anaerobic power, muscle strength, power, and speed. If you are a marathon runner, you need to train aerobically (long duration, moderate intensity).
Anaerobic exercise means that the body burns fuel without oxygen – it doesn’t need it. The body will use stored up carbohydrates (glycogen/glucose) for energy instead. This is why anaerobic exercise is short duration (less than 90-seconds) and moderate-high intensity. Squats, ladder drills, reverse lunges, push ups, etc are perfect examples. Anaerobic training improves muscle strength, power, mass, and speed of movement. While increasing anaerobic power, you can also increase aerobic capacity, thus – anaerobic training improves both systems without any loss of muscle mass or strength!
In the 30 Minutes of Everything program we mix up your workouts and the intensity. Some days may be more aerobic and other days more anaerobic. On the days that are anaerobic (high intensity, more muscle demand, 80-90% MyZone workouts), we give you a longer rest period. This rest period is necessary to refuel. Without a rest period, you will crash. Your performance will go down. You will make mistakes. Your form will suffer. You increase your risk of injury. Rest is necessary. In our class, the rest interval for the higher intensity workouts is less than one minute. Athletes training for maximum strength and explosiveness will rest 3-5 minutes between sets!
I know sometimes you feel like you just want to keep going in class and push through the workout and burn the most amount of calories. In reality, you will burn more calories and get better results if you rest. You can train harder with rest and elevate your metabolism for hours after the session, not just during. That is an added bonus of training at higher intensities with rest intervals. The next time you feel like pushing through a rest interval, don’t. Take the rest. Refuel. Push hard through the next set! You will feel so much better, during and after your workout!