How running 61.8 miles reduced my body fat by 22.3% in 1 month
Last month I decided it was time to start an experiment:
What does running do to my body, especially my weight, body fat percentage, and muscle mass?
As it turns out, it helps with reducing weight, body fat percentage, and it even increases muscle mass.
My body fat percentage reduced by 22% that month, and my muscle mass increased by 4.5 Lbs.
I’ll show you precisely what happened week by week. I’ll also give you an overview of how I did exercise wise and food-wise.
So let’s start right now:
I’ve been running for about 25 years now, so I consider myself an experienced runner. But last few months, I was so busy with finishing my master’s degree in Manual Therapy that I didn’t have much time to run.
Therefore this was the perfect time to perform the experiment.
I started by measuring my body characteristics with our body scale.
These were my stats:
- Age: 34
- Height: 6 foot 4 inches
- Weight: 193.5 lbs
- BMI: 22,6
- Body Fat percentage: 22,2%
- Muscle mass: 143 lbs
- Visceral fat: 5%.
The plan was to train three times a week covering 6.2 miles each training.
I wanted to keep my heart rate between 70%-80% of my maximum heart rate. For me, this is a range where I can run for a long time without damaging my muscles too much. That way, I made sure that I could run three times a week without overdoing it.
If you’re starting with running, I would advise you to stay at 60% of your maximum heart rate. That is also the ideal zone for fat burning.
To measure my heart rate during the run, I use my Polar watch. It measures my heart rate, distance, pace, and calories. It even shows useful overviews, which I’ll show you later.
For running, I use New Balance running shoes. I used to run on Asics shoes, but I found out that New Balance gives more support. When you weight 120 pounds, that’s fine, but for me, Asics shoes are too soft. New Balance shoes provide more support and even improves my speed.
Results after week 1
The first week, I had to get used to running three times a week. Since I didn’t do that for so long, I encountered some muscle sourness during the first week.
I did notice that during the week, running became easier already. My heart rate decreased during the exercises, but my speed was still the same. That shows my improvement.
My eating habits were not so good this week. Because it was Easter, we did buy chocolate Easter eggs. It’s a tradition to have these, but they are not helpful for my weight due to the number of calories and the high amount of sugar they contain.
That showed in my results of the first week:
- Weight: 192 pounds
- BMI: 22,5
- Body fat percentage: 23,3%
- Muscle mass: 140 lbs
- Visceral fat percentage: 5%
As you can see, I lost 1,5 lbs that week, according to my scale. But when you look closer to the stats, it’s not as good as it seems.
My body fat percentage rose by 1,1%, and my muscle mass decreased by 3 lbs.
So even though my total weight reduced, I’m still not happy with the results.
I blame the high amount of chocolate I ate that week. If I wouldn’t have done that, I’m sure the stats would be better.
It’s not a reason to give up or question myself. The chocolate is gone, and we’re not buying new ones. Next week will be better.
I finished the first run of 6.2 miles in 1 hour and 25 seconds. My average heart rate was 146, with a maximum heart rate of 156, and I burned 941 calories.
Results after week 2:
The second week the running went not so good. I had a lot of stress during the week due to a school exam. I noticed that my heart rate was higher both at rest and during exercise this week.
I could tell by my running results. Due to the stress, I struggled to run as fast as I usually would at the same heart rate. It shows that stress hurts your training results.
Fortunately, stress doesn’t influence my eating habits. I don’t binge or turn to comfort food to cope with stress. Exercising is my way to reduce stress. After running for an hour, I feel reborn and don’t notice the stress as much as I did before I ran.
Also, walking outside in nature release stress effectively.
These are the results of the second week:
- Weight: 192.5 lbs
- BMI: 22,5
- Fat percentage: 19,5%
- Muscle mass: 147.3 lbs
- Visceral fat: 5%
As you can see, my weight increased by half a pounds. That doesn’t look good, but again, it’s not as bad as it seems.
My fat percentage dropped by almost 4%. Furthermore, my muscle mass increased by nearly 7,5 pound. That’s a lot of muscle mass in one week.
It shows that these measurements are not as accurate as we would like them to be. There is no way that I’ll lose 4% of body fat in one week. It’s also impossible to gain 7,5 pounds of muscle in one week through running. It shows that a scale is not accurate enough to weigh yourself often. It will show you mixed results that can discourage you if you take them too literally.
That’s why I wouldn’t recommend to weigh yourself more often than once a month. That way, you will see real results. Also, your pants size is a much more accurate way of measuring progress.
Results after week 3
The third week I noticed that running becomes easier every week. My aerobic threshold slowly rises. That means that I can run faster without going out of breath. It results in burning more calories during my run because I’m able to run faster.
Also, my muscle is getting used to the effort they have to deliver. I feel less soreness after running, and even the next time I run. That means that my muscles get stronger.
These are the results of the third week:
- Weight: 191.1 lbs
- BMI: 22,3
- Fat percentage: 18,1%
- Muscle mass: 148.8 lbs
- Visceral fat: 5%
As you can see, I’ve lost another 1.4 lbs this week. Running is resulting in fast weight loss at this moment. I also reduced my fat percentage by 1,4% and increased my muscle mass by another 1.5 lbs.
It shows that all my metrics are getting better, not just my weight. That means that I’m getting healthier every week. It also shows that you can’t expect results in the first week. Consistency is key. Eating healthy and exercising regularly will grand results if you stick to it.
Results after week 4
The last week was not my best week foodwise. This week we celebrated my brother’s bachelor party.
It was a day where I ate a lot of food and drunk a lot of coca-cola (I was the designated driver). I also only ran twice that week instead of 3 times because I didn’t have the energy after the bachelor party to go for a run since I only slept for 3 hours.
It’s not a bad thing to skip one training to be able to enjoy life. I’ll pick up next week and continue the excellent work. That way, I’m able to live a lifestyle that I can continue for the rest of my life. If I’m not allowed to enjoy these things anymore, I won’t stay motivated to keep doing what I have to do to succeed.
These are the results of the third week:
- Weight: 191.4 lbs
- BMI: 22,4
- Fat percentage: 19.1%
- Muscle mass: 147.5 lbs
- Visceral fat: 5%
As you can see, my weight increased slightly with 0.3 lbs. My fat percentage also increased by 1% and my muscle mass decreased by 1.3 lbs.
You can see that one day of bad habits can ruin an entire week of good eating and exercising. That’s why you should reduce cheat days to an absolute minimum. Only allow one if you have an excellent reason, but don’t have a cheat day because you want to have one. It’s better to enjoy a pizza when you’re out with friends then when you’re by yourself at your couch.
The last run I did this month was 6.2 miles in 59 minutes and 12 seconds. My average heart rate was 146 beats per minute, with the highest heart rate of 157 beats per minute. During that hour, I burned 922 calories.
During these four weeks of training, my body composition changed a lot.
My weight dropped by 2.1 lbs. That doesn’t seem like a lot, but the real difference comes from my muscle mass and fat percentage. My muscle mass increased by 4.5 lbs in 4 weeks. So don’t tell me that aerobic exercising doesn’t build muscle mass.
My fat percentage dropped from 23.3 to 18.1, at its lowest. That is a decrease of 22.3% in four weeks. If you convert it to weight my fat mass reduced from 44.7 lbs to 34.6 lbs, that’s a reduction of 10.1 lbs or 22.6%.
You can see that aerobic exercise like running, walking or cycling reduces bodyfat pretty fast, as long as you eat clean and healthy.
I know that if I continue this journey, I’ll lose even more weight and also my fat percentage continues to drop. It shows that consistency is critical.
Now I want to hear from you
Did my results inspire you to start exercising as well?
I know that you can have the same results as me when you start exercising.
Let me know if you need a guide to start running yourself.
If so, I’ll create a guide to help you.
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