What’s your exercise intensity level? Are you pushing yourself or just going through the motions? Are you working outside of your comfort zone? If you’re not, you should be. Here are 9 reasons why you should increase your exercise intensity.
Improved health and longevity is always a good motivator. Average exercise intensity is associated with reduced coronary heart disease independent of the total volume of physical activity . Exercise intensity is also inversely correlated with all cause mortality. Vigorous exercise improves longevity . In other words, the more intense your exercise, the lower your risk of premature death.
One of the biggest benefits for increasing your exercise intensity comes from hormone stimulation. High-intensity exercise stimulates the release of insulin-like growth factor (IGF) . It also stimulates the release of growth hormone and testosterone, two of the most powerful hormones when it comes to fat loss and building muscle  .
Last but not least, exercise intensity and your thyroid hormones are directly correlated. TSH, T4, and free T4 all rise in step with intensity levels . Thyroid stimulating hormone (TSH) stimulates the release of T4, which converts to T3 – the more bio-available thyroid hormone responsible for stimulating metabolism. All of these hormones are stimulated in response to physical activity, but they are released in proportion to exercise intensity levels.
Body Fat Reduction
Who doesn’t want to drop a little body fat? High-intensity exercise induces more pronounced body fat reductions compared to endurance training, even when burning fewer calories . Study after study has shown that high-intensity exercise is superior to moderate-intensity when it comes to losing body fat. Just one of the many reasons you should forget about the fat-burning zone.
Greater After-Burn Effect
High-intensity exercise provides a greater after-burn effect, also known as excess post-exercise oxygen consumption (EPOC) . When we exercise we create an oxygen debt. When we finish exercising, our bodies work to erase that oxygen debt.
Your body uses calories to restore itself to homeostasis. Cellular repair, fuel replenishment, re-oxygenation of blood, and bringing the heart rate back to normal are all functions the body performs after high-intensity exercise.
Exercise at intensities above 40% of V02 max is required in order to trigger the metabolic processes that are responsible for prolonged EPOC extending beyond 2 hours post-exercise. In addition, there is an exponential relationship between exercise intensity and total EPOC .
Effects on Eating
The intensity of your exercise also influences your eating patterns. While there is no significant change in hunger, high-intensity exercise favors negative energy balance to a greater extent than low-intensity exercise . High-intensity exercise also causes a delayed onset of eating .
Effects on Workouts
No need to spend hours in the gym if you’re exercising at a high intensity. The rise of HIIT workouts has made it possible for just about anyone to get in an effective workout in 20 minutes. Who can’t wake up 30 minutes earlier to get in a workout?
Besides the positive effects on workout times, you also have decreased boredom. I personally have a hard time getting bored when I’m sprinting back and forth across the football field. On the other hand, put me on a treadmill, and I can’t stop staring at the timer. Is this ever going to end?
I think we’ve all experienced the “runner’s high” at some point in our life. If not from running, it was from some other intense exercise. Exercising at 80% of V02 max significantly elevates endorphin levels . Pushing yourself to your physical limits by increasing your exercise intensity stimulates the production of feel-good chemicals like endorphins.
Improved Insulin Sensitivity
Good insulin sensitivity is vital for good health and fat loss. Trying to lose fat in the presence of constant high insulin levels will force you to fight an uphill battle.
You can improve your insulin sensitivity through nutrition, but you can also improve it through exercise. Insulin sensitivity is higher in individuals who participate in vigorous activity 5 or more times per week as compared to those who rarely or never participate in vigorous activity .
Improved Cardiovascular Fitness
High-intensity exercise is superior to moderate exercise for increasing V02 max . V02 max is the amount of oxygen a person can transport and use during exercise. The more oxygen you can use, the longer and more intense your exercise can be. Your cardiovascular fitness is significantly improved with high-intensity exercise as compared to moderate-intensity .