Growing up I was constantly teased for being skinny. From my teenage years on up I tried just about everything to gain weight and muscle. So when I learned about kickboxing I thought to myself “all that punching and kicking should build some serious muscle, right?” But the more I fought that punching bag, the skinnier I got. I loved all of the benefits of kickboxing, but bulking up and building muscle was not one of them.
I discovered that unfortunately, although Kickboxing is an exceptional cardiovascular workout, it does not integrate enough increasing resistance to build a significant amount of muscle or gain weight. But it will burn calories to help melt away fat, giving the body a more toned look overall.
I have always had a burning desire to put on some serious muscle. I even resorted to wearing extra layers of clothes to look bulkier. (Imagine how fun THAT was on those hot summer days.) So after the let down of not seeing any gains, I looked into the science behind it. If you want to know why you can’t build a lot of muscle kickboxing, and what you can do to change that, read on!
Kickboxing is Not Strength Training
Scientific research tells us this:
Building a significant amount of muscle requires the muscles to be continually challenged by increasing levels of resistance or weight. When muscles fibers encounter this type of challenge, they sustain small tears which then must be repaired.
Every time the body repairs and rebuilds the muscles that have been “injured” or worked out, the muscle fibers slightly increase in size. This process is called muscle hypertrophy. In order to truly see a visible change in muscle mass, it takes many weeks of challenging those muscles with consistent and increasing resistance.
As our muscles get stronger, the volume and weight needed to get to the point of lifting to failure increases. Lifting to failure, or lifting a weight until your muscles can’t possibly do another rep, is key to building muscle.
This verifies for us that kickboxing cannot build enough muscle to really see visible growth. In kickboxing there is not a continual increase in resistance that is needed to challenge the muscles enough to cause hypertrophy (muscle breakdown and regrowth). Without this process, muscle growth does not occur.
Beginners could see a slight change at first because they’ll be challenging their muscles in new ways, therefore causing some hypertrophy. But once the muscles have adjusted to the new kickboxing exercises and are no longer challenged by the necessary increasing amounts of resistance, that muscle growth will cease.
Further evidence of this is presented in a five week study by pubmed.gov, in which fifteen people trained in kickboxing for an hour a day, 3 times a week while a control group of fifteen people abstained from any training.
In this study PubMed analyzed the effects of kickboxing training on body composition. The study concluded that body composition, therefore muscle, mass did not show significant change in either the kickboxing group nor the control group over those five weeks.
How Can I Build Muscle While Kickboxing?
If you really want to bulk up and gain muscle mass, it’s recommended that you incorporate weight lifting into your weekly workout schedule. If you’re sparring or using a punching bag, your trainings shouldn’t be on consecutive days- to avoid overuse injuries.
This will leave a good window for weight training in your workout routine. Kickboxing one day, weight lifting the next will ensure you get both your cardiovascular training and strength training in.
It’s extremely important to also consider your diet and nutrition if you are wanting to bulk up. As you continue to train in kickboxing, you will be torching a lot calories. If you combine this with a diet that keeps your calories in a deficit, you will lose weight rather than gain muscle mass.
In order to put on more mass, you will have to make sure you are getting enough calories, and specifically protein in your diet. Protein is the macronutrient that feeds your muscles and helps them to grow. American College of Sports Medicine (ACSM) recommends eating 1.2-1.7 grams of protein per kilogram of body weight to increase muscle mass. Increasing calorie intake is important as well. A surplus of 500 calories a day can equal an increase of a pound of muscle a week. Use a Calorie Calculator to find out how many calories your body needs to maintain or increase your body weight. This is my absolute favorite Calorie Calculator.
If it Doesn’t Build Muscle, What does Kickboxing Do For Your Body?
Let me count the ways! Kickboxing is a super beneficial sport and workout for so many reasons. One of the best reasons- it can completely change your body!
Kickboxing may not increase muscle mass, but it does improve muscle strength. In the PubMed study mentioned previously, the subjects’ strength was measured before and after the study. There was a substantial gain in muscle strength in the kickboxing group after 5 weeks of training.
Because we use every major muscle group in kickboxing, you can also gain strength in nearly every part of your body. Kicking engages the quads, hamstrings, glutes and abs. Punching activates the delts, biceps, triceps and core muscles. Even the calves get a great workout when your having to stay light on your toes throughout your workout.
So you won’t see a gain in mass, but you will see a gain in power and strength. To read more about exactly how the muscles are worked and strengthened in kickboxing check out this article.
This study also concluded that “the kickboxing group showed significant improvement (p < 0.05) in upper-body muscle power, aerobic power, anaerobic fitness, flexibility, speed and agility.” Quoted from PubMed.gov. This study illustrates how kickboxing can truly upgrade your fitness level in nearly every way.
Not only does kickboxing improve your aerobic and anaerobic fitness, strength, and flexibility, it can also change the way your body looks. You can burn an average of 400 calories an hour while kickboxing, not to mention an afterburn that improves your metabolic rate which will burn even more calories throughout the day.
With all of this calorie expenditure, you can shed fat pretty quickly. If you burn more calories than you eat in a day you will be in a calorie deficit. If you are in a deficit of 500 calories a day you can burn a pound of fat a week! Getting to a lower body fat percentage allows your body to show muscle definition and will leave you looking stronger and more toned.
So overall, kickboxing on a regular basis can change your body in several ways:
- Increased muscle strength
- Improved flexibility and agility
- Enhanced aerobic power
- Improved speed
- Improved anaerobic fitness
- Increased muscle tone
- Promotes fat loss/weight loss
How Often Should You Kickbox to See Results?
The evidence proves that kickboxing produces major changes in your fitness and body composition. But how long does it take to see those results and how often should you kickbox to see those changes?
Studies show that after participating in a kickboxing program 3 days a week for five weeks, most people will show a significant increase in nearly all areas of fitness. But if you want to lose weight, especially fat, you will need to also incorporate a diet that will put you in a calorie deficit.
As I explained previously, the best way to do this is to use a calorie calculator to determine the number of calories your body needs. If you kickbox 3 days a week and lift weights on the alternate days, you can burn about 400 calories a day.
If your diet consists of a daily calorie deficit of just 100 calories a day and you add on daily kickboxing and weight lifting, you can easily put yourself at a total deficit of 500 calories a day. You can lose a pound of fat per week if you maintain this 500 calorie deficit. Within a couple of months you can be 10 pounds lighter. And in a year you could be down almost 50 pounds! Stick with it- slow and steady wins the race!