Burning a lot of calories doesn’t take a lot of effort. But it does take more effort than you think. If you’re like me, you’ve looked at those graphs that tell you how many calories you can expect to burn in 30 minutes. Or an hour. It’s seems pretty impressive. Riding my bike for 60 minutes will have me burning calories in no time flat. If I do the math I’ll be hot and skinny for summer. Obviously, it’s more complicated than that.

But for now let’s just focus on the amount of time it take to burn calories doing realistic workouts that build muscle, burn calories and improve the cardiovascular system. That means lifting weights, doing functional exercises and performing some cardio to get the body warmed up and the heart up to speed.

Burning a lot of calories doesn’t take a lot of effort. But it does take more effort than you think.

Don Vaillancourt

The challenge with burning calories is that its expenditure is not linear in any meaningful workout session. It depends on the exercise, the intensity of that exercise and the duration of that exercise. But the point is that doing twenty burpees when you’re fresh at your highest intensity possible will not burn as many calories as one would think.

The graph below is an example of what my caloric expenditure would look like on my stationary bike. Below is just an example as my sessions are always different, but it reflects how many calories my body will burn. As you can see below, the first 150 seconds of the workout I’ve only burned 18 calories. At 5 minutes, less than 50 calories. But at 15 minutes, I’ve burned almost double what I burned at 10 minutes. So at some point caloric expenditure becomes exponential.

When I do decide to go all out on a stationary bike session, I’ll usually start out at 60 RPMs (pedalling) and ramp up to 80 RPMs rather quickly. By the five minute mark I’ll be at my maximum of 120 RPMs. At this speed, I need to control my breathing so that I can maintain the pace all the way through. And my BPM should also be going up constantly.

The first time I did this experiment, the next morning I could not move; my central nervous was exhausted. The whole day I was effectively moping around like an old man. I did the experiment a few other times, but not as intensely, and my body’s fitness slowly improved.

I did other combinations of cycling, functional workouts and weight lifting. The outcome was similar in all cases. Although, sometimes it would take longer before the line curved up. Different exercises exert different intensity against the anatomic nervous system. Working out with 40-50% my 1RM at an increased pace yielded the max result for me.

What I’ve learned from my experiments is that working out for a minimum of 20-30 minutes causes your body, heart and anatomic nervous system to get tired. The more tired they get the harder they must work to get the muscles the resources they need to function. And when my heart rate reaches 80% MHR, then calorie burning is about to get serious. The goal to maximum caloric expenditure is to get your heart rate to at least 70-80% MHR depending on fitness level. I can reach 90% MHR, but can sustain 70-80% when doing functional exercise. I can maintain above 80% doing stationary cycling.

The key to get to MHR isn’t to work out like a maniac. I used to think that going from one exercise to another like the world was going to end was the key to get the heart rate up. But it isn’t. I discovered while using the rowing machine that I was burning more calories and was more efficient if I rowed 500 meters in 2:26 minutes than trying to do it in 2:02 minutes. So it’s more important to pace yourself. My heart rate didn’t tank if I took a few seconds longer to switch exercises. As soon as I started working out again, the heart rate would go back up again.

The goal of working out is to increase your muscular strength, strengthen your heart and improve breathing and lung capacity. One of these will always be your weak link. Mine is my breathing and lung capacity. So I need to work out hard enough so that I can sustain my workout, but not so hard that my lungs are constantly forcing me to stop. I want to work smarter, not harder.

So to recap:

• Workout at 45-50% maximum capacity. but at a higher pace
• Workout 20-30 minutes to warm up
• Use a sustainable pace, but push yourself until your lungs or muscles hurt a little. If your heart starts beating hard too fast too soon, slow it down.
• Once your heart reaches 70-80% MHR, keep going for another 15-20 minutes at the same pace.

I hope this information will help someone just starting out and wants to be smart about getting fitter. Be patient, persist and the rewards will come.