Are High- or Low-Intensity Workouts Better?
Go faster. Do more. Work harder. Be better. Sound familiar? Does this sound like a gym you’ve been to or like your life, generally? Both?
High-intensity training is all the rage. From CrossFit to HIIT to Insanity, people all over the world are being left in gasping sweaty piles at the end of their workouts. For what? Is the hype worth it? Do high-intensity workouts really produce high-quality results? Sorry to build it up for this let-down of an answer, but the answer is that it really depends on your individual health and lifestyle.
High-intensity exercise can improve strength, power, and endurance. It can also improve insulin sensitivity, digestion, nutrient absorption, bone density, and blood sugar regulation. It can even lead to the loss of unhealthy fat and excess weight. Know what else it can do? It can put unnecessary stress on the body. I’m sure you noticed the strategic word in italics: CAN. All of these things, both positive and negative CAN happen. It depends on who you are and what is going on in your body. If you want to find out where you might fall, read on…
The human body is actually freaking amazing. It is made up of 50 trillion cells (this number is so big I wrote it out in words because it’s proven to cause dizziness if you see that many zeros in one place). To put this in perspective, one trillion seconds (just 1) is 32,000 years! So, needless to say, 50 trillion cells is a lot of freaking cells. Okay, so what’s the point? I already said it but the point is that our bodies are really freaking amazing! All of these cells have a fine-tuned system to communicate with each other so we can run, jump, speak, eat, and play. Here is where we start to differentiate ourselves into the categories of who might benefit from high-intensity exercise.
Our cells need nutrients to communicate effectively with each other. The only place we get nutrients is from the food we consume. Lots of different factors may impede the absorption of these nutrients, but one of the main ones is STRESS. Our modern bodies are over 99% the same as our cavepeople-ancestors, which may not seem noteworthy, but I mention it here because really the only time our ancient ancestors ran at a fast pace was to escape danger or pursue food. So yes, there were short bouts of physical stress (which we might label as high-intensity moments) but otherwise, they were primarily engaged in low-intensity activities. Modern people, on the other hand, run fast for fun… for “fitness.” When we amp up our physical activity to short bursts of speed and intensity, we might intellectually know it is for our health, but our body doesn’t know that; it goes into fight-or-flight mode to survive.
When our bodies are healthy* and we are relaxed we can handle the stress of a high-intensity workout and reap all of those positive benefits I listed above: improved strength, power, insulin sensitivity, digestion, nutrient absorption, bone-density, and blood sugar regulation, and the loss of unhealthy fat and excess weight. When we are sick or chronically and frantically stressed out and over-taxed by the perceived pressures of our lives, however, this high-intensity exercise is not handled well by our body-systems. We may be burning loads of calories but still gaining weight because our body is constantly in survival mode and it stores up lots of fat so we have it when we “need” it for battle. By contrast, when we are calm, we can use body fat as fuel for energy.
The irony here is that the stressed out, frantic people are often those who are drawn to the high-intensity workouts because you can “get such a good workout” and “burn so many calories” in such a short period of time. It fits so nicely into their jam-packed schedules. But their bodies are already taxed from the high levels of adrenaline and cortisol surging throughout their stressed-out days; it is hard for them to recover from a strenuous workout that breaks down muscle fibers and challenges the heart and lungs. These people are often over-trained, a condition with symptoms such as mental and/or physical fatigue, irritability, impaired sleep, and difficulty focusing. Healthy people know to rest, refuel, and recover and the taxes on their systems during a workout ultimately make their bodies stronger and increasingly more able to bounce back from physical exertion.
This is why I promote a balanced approach to exercise. Unlike most other trainers that tell you to work out 6 days a week, I say to do something low-intensity (and ideally outside!) at least two days a week. This can be a hike or a bike ride along the river, yoga or bouldering, kayaking or SUPing, even a slow, leisurely jog in the park. It could even mean doing a workout and taking a more low-intensity option for movements, like box steps instead of box jumps or a weighted PVC pipe instead of a weighted barbell.
Low-intensity activity has more benefit than just calming us the F down. It still gets our blood flowing, improves endurance, produces endorphins, and improves our heart health and metabolism. The key here if you are a Type A adrenaline junkie who doesn’t consider it a good workout unless you are wrecked afterward is to retrain your brain into thinking of all “movement” as “exercise.” Slowing down doesn’t mean you are weak; it means you are adding variety to your routine and building a solid foundation so your body doesn’t crumble later on.
So to answer the question: Should you do high-intensity or low-intensity workouts? DO BOTH! Unless you are chronically stressed, frazzled, and fatigued. Then scaling it back and spending some quality time deep-breathing in nature might be the best “workout” you’ve ever had.
