Sure exercise is about health benefits but a major aspect is gaining awareness of how your body functions and developing a sense of connectedness to your physical body. Sometimes, folks jump into exercise (literally) assuming they have to work themselves to exhaustion or kill themselves at the gym. If they’re not losing weight, they might try working harder and longer. The result is usually they start hating exercise and give up. But we can bring physical activity into our lives in different ways and use strategies that help us work more effectively and efficiently instead of just wearing ourselves out and quitting.
My goal for my experiment was a simple and straight-forward test. After doing 30 minutes on the stepper for awhile, it was already seeming like a drudge even if it did make me feel great! Cutting the time in half was an appealing idea but would I be doing the same work?
The two week Cardio Workout Showdown is complete and what did it show? Two shorter exercise sessions in a day DID result in a higher total calorie burn by day’s end than one longer exercise session. That is the simple answer and remember that this little experiment was done under very basic conditions. To recap for you, I’m 54 years old and 5’6″ tall. Over the past two weeks, my weight changed by only one pound which could be attributed to fluctuation. I’ll talk about that later. First, let’s consider the calorie burn.
I want to extend one caveat. My BodyBugg is several years old now. I’m not sure if it’s exactly accurate anymore but I think it can be used to see relative change especially since the calorie burn for the first week stayed so consistent. May 3 and May 12 were higher burn days that can be attributed to higher step counts for those days. I wanted to keep things consistent but I still have to walk to get around!
The first week calorie burn averaged 2184 per day for seven days with one 30-minute cardio workout session. The second week calorie burn averaged 2305 for seven days with two 15-minute cardio workout sessions, an average daily increase of 121 calories. That’s about 5% per day higher. It’s not a very big difference and for pure calorie burning, I could have made it up with just a little bit more walking so I think the results of this experiment come down to considering convenience, personal priorities, and what’s most likely to keep you exercising.
First I’d like to cover what I think accounts for the calorie burn difference. I think it has to be EPOC, the Excess Post-Exercise Oxygen Consumption. Some folks call it the “afterburn.” I always liked calling it the “Freeburn” because it’s like burning extra calories for free. After you exercise, your body continues to burn calories at a higher rate depending on the intensity and duration of your exercise session.
The calorie burns for two 15-minute sessions added up to a little higher total than one 30-minute session. So that’s not really it. A lot of people might come out the same by the end of the day. The difference has got to be the EPOC. I worked pretty hard on that stepper. In 30 minutes I can get my heart up to the 160s; in 15 minutes I’d reach the 140s. I’d still get good and sweaty for the shorter bouts. I tried to pump harder when I knew I wasn’t going to have to pace myself for a whole half hour. So I think the real payoff here was that I got TWO EPOC afterburns in a day instead of one. I can’t measure this but I would guess—and here’s what I think is the real key to the whole experiment—that the afterburn period for the 15 minute sessions at a strong intensity lasted about as long or pretty close to the duration of the EPOC for the 30-minute sessions that were lower intensity overall. This is kind of an intensity vs. endurance comparison. I worked longer for the 30 minute sessions but I worked harder for the 15 minute sessions, resulting in what I am going to theorize was a fairly similar EPOC period afterward. And two in a day are better than one! So, I think that’s where the extra calories come from.
I happened to read this weekend that there HAVE been studies (of course!) on just this kind of thing. One study had subjects do one 40-minute exercise session while others did four, 10-minute exercise sessions. The test subjects who did four exercise sessions improved their fitness to a greater degree and that will translate into overall better health. Some viewpoints on the concept insist that you can take the “banking” style approach—multiple small deposits will add up to the same as one big deposit.
What’s the real consideration here? As I always say DO WHAT WILL WORK FOR YOU. I have to admit I can’t really decide which approach I liked better! Doing one exercise session gets it out of the way but I have to trudge through a whole half hour. I found I did have a better attitude about breezing through a quick 15 minutes. But I had to make time TWICE every day and I got sweaty TWICE every day. I have a great advantage that I work for myself at home and have a LOT of flexibility over my schedule! Multiple exercise bouts in a day may not be practical for a lot of folks.
For myself, I also have to consider if I get the same quality cardio workout from a shorter bout. I like to run my heart rate up and my fitness level is very good so I can’t get to those higher rates unless I work longer. My heart conditioning is so good that just stopping to take a quick drink makes my heart rate plummet. (Rapid recovery is an indication of conditioning.) A good strategy FOR ME might be three longer sessions per week to put the focus on heart rate conditioning and multiple daily sessions the rest of the week to keep that calorie burn going and my fitness level strong overall.
I think a lot of people don’t exercise because they dread what they think will be a long, exhausting workout session. And many people think to improve their fitness or get their weight down, they have to put in more and more time so eventually it becomes an ordeal and they want to quit. But you CAN work smarter. Armed with information, do what you think will work for you. Would three 10 minute exercise sessions in a day appeal to you far more than one 30 minute session? Will you work to the highest intensity you can at each of those 10 minute sessions? Are the logistics practical for you? Then give it a try if it will make the difference between getting regular physical activity into your life or not! Do what you think will be the foundation of a regular exercise routine for the on-going future. Killing yourself in the gym for a few months might change your appearance in the short-term but real fitness has to be for life.
Here are my stats for the past two weeks. I will address the total calorie burn and my weight in my next blog post.
May 1: 2190 calories, 10,192 steps. 232 calories burned in 30 minute cardio workout session.
May 2: 2175 calories, 10,460 steps. 228 calories burned in 30 minute cardio workout session.
May 3: 2273 calories, 11,826 steps. 247 calories burned in 30 minute cardio workout session.
May 4: 2182 calories, 9032 steps. 239 calories burned in 30 minute cardio workout session.
May 5: 2150 calories, 9686 steps. 243 calories burned in 30 minute cardio workout session.
May 6: 2167 calories, 9899 steps. 230 calories burned in 30 minute cardio workout session.
May 7: 2155 calories, 9786 steps. 235 calories burned in 30 minute cardio workout session.
May 8: 2290 calories, 10,169 steps. 125 calories burned in first 15 minute cardio workout session, 165 calories burned in second. Seemed like an aberration. I was interested to see if that would happen again. It did not.
May 9: 2300 calories, 10,102 steps. 125 calories burned in first 15 minute cardio workout session, 150 calories burned in second. Another high second session. Did I work harder at the end of the day? It was weird that I burned exactly 2300 so I took a picture.
May 10: 2342 calories, 10,247 steps. 132 calories burned in first 15 minute cardio workout session, 139 calories burned in second. Higher day even though I did not put in lots of steps so I’m not exactly sure why.
May 11: 2252 calories, 9841 steps. Average day’s calorie burn is remaining above the average of the first week. First cardio session 128 calories. Forgot to record the second session!!
May 12: 2445 calories, 12,0004 steps. Highest calorie day yet can be attributed to the highest step count. In addition to what the Bugg logs on the Stepper, I’ve been making sure to walk up to around 10,000 steps total for the day. Yesterday I had more places to go and happened to put in more steps.
May 13: 2212 calories, 10,108 steps. 128 calories burned in first 15 minute cardio workout session, 124 calories burned in second.
May 14: 2298 calories, 10,301 steps. 127 calories burned in first 15 minute cardio workout session, 134 calories burned in second.