We all know running is good for us, any exercise that gets our heart rate up and gets us moving will be a big positive for our health. But what if our primary goal is to change our bodies? Maybe we want to get toned, lose weight or build some muscle. Can running help with that? Are there any unwanted changes to our body from running? Let’s find out. Join us as we show you how running can change your body.
Taking up running is going to change your body, no doubt about that. Especially if you have led a predominantly sedentary life until now.
As a form of cardio exercise, running will trigger various physiological processes that will lead to changes in your body composition.
Some of these are very welcome, and you may be targeting these directly, but some may not be so welcome.
So let’s dive in and take a look at how running can change your body. Spoiler alert….it’s mainly good news, there are very few unwanted changes.
Running Can Give You Toned Thighs, Big Calf Muscles and a Great Butt.
Will Running Tone My Thighs?
Running works the upper leg muscles quite effectively, but because you are only working with your own body weight, most people are unlikely to build big upper leg muscles.
Building muscular legs would require greater load-bearing exercises such as resistance training with weights in the gym. Running will generally result in lean muscle growth only.
Since we aren’t building big muscles as such when we are running, the cardio effect will generally result in lean muscles and reduction of body fat in the thigh area.
This is why running can actually tone up the thighs, giving runners that conditioned athletic look.
Does Running Build Big Calf Muscles?
This is one area where people are going to differ greatly. Some people will have toned, lean calf muscles and others will end up with really large calves.
As a general rule, long-distance runners will have leaner calf muscles, and those who run shorter distances have a propensity to build larger calf muscles. The calf muscles are more actively engaged when running on the forefoot, which is a characteristic of sprinting or running hills, and therefore tend to build bigger calf muscles.
Personally, I do one long-distance run each week and at least two shorter workouts that may incorporate hills, stairs or sprinting, and over the years I’ve developed fairly decent calf muscles. My other leg muscles are fairly lean.
So how does calf size affect running performance? Having large calves will definitely help sprinters by increasing launch power, and may also contribute to faster speeds over short distances. For long-distance runners, large calf muscles may in fact harm your speed.
If you like the look of big calf muscles and want to add some resistance training to your exercise regime to build them up, just know that if you predominantly run long distances, it may negatively affect your race times.
Will Running Give Me a Great Butt?
To answer this question, I’m going to give you a short human physiology lesson.
The butt, or let’s be a little more erudite and use its proper muscular clinical name, the Gluteus Maximus (GM), glutes for short, will develop according to the type of running you do.
It comes down to the type of muscle fibres you engage as you run. There are two types of muscle fibres, Type 1 or slow-twitch fibres and Type 2, fast-twitch fibres. Type 1 fibres are leaner and built for endurance, whereas Type 2 fibres are larger and stronger.
Long-distance running generally engages the Type 1 fibres and therefore results in a more lean muscle composition. Sprinting and hill work requires more power and will engage the Type 2 fibres. Consequently, when you work a muscle hard in this way, it breaks down a little and then rebuilds bigger and stronger during the rest periods after the workout.
So what does this mean for runners in terms of butt-building?
Long-distance running which is effectively a long cardio workout will break down fat and build Type 1 muscle fibres, resulting in a lean butt. Sprinting, stairs and hills etc will engage Type 2 muscle fibres and tend to build the GM muscles, resulting in a bigger, more muscular butt.
Who knew, you can dial in what kind of butt you want by choosing the type of running you do. Another example of how running can change your body.
Running Will Help You Burn Calories and Lose Weight.
As mentioned above, running, particularly long-distance running, is a cardio exercise. Cardio workouts are excellent for their ability to use up a lot of calories and burn fat. But how much fat will it burn and what type of running is the best if weight loss is your primary goal? Let’s take a look.
There are three important ingredients we think you need to consider in your weight loss journey-
- Exercise. In this case running, but whatever you do it should include cardio, and it should be for at least 30 minutes each session.
- Diet. Whole, fresh foods, less (or no) meat, less (or no) dairy, less highly-processed foods and a lot less fast food.
- Consistency. Working out three times a week with other less intensive physical activity, such as walking, in between.
The important takeaway here is that you are going to need to focus on your diet as well as lacing up your trainers. Running alone may not deliver your goal weight, especially if your diet is poor. (Looking at you Western world).
If you are a new runner just starting out, my tip would be not to worry too much about your diet at first. Just getting used to running will be challenging enough for you without changing up your diet as well.
For beginners, we have a great free Couch to 5k Run Plan to launch you safely and enjoyably on your running journey.
Once your body has adjusted to regular running, then it’s time to look at your diet. One thing at a time to ensure success, right?
What Type of Running Should I do For Weight Loss?
The secret of using exercise to promote weight loss is getting that heart rate up for a prolonged period of time in regular, consistent workouts.
Sprinting and hill or stair running will deliver short, sharp increases in heart rate and build strength and stamina. As previously mentioned, this type of workout also has the potential to build larger leg muscles. This may not be desirable if your focus is on weight loss.
Long-distance running or sustained running which elevates your heart rate to a level you can maintain over a set period of time may give you better weight loss results.
Aiming for about 30 minutes of constant running will give you that prolonged heart rate boost you are looking for, and the added bonus of raising your metabolism, which can continue for many hours after you have completed the workout.
How Much Weight Can I Lose By Running?
To effectively lose weight, you are going to need to put your body into what is known as a calorie deficit. That means we are burning more energy (calories) than we are consuming.
But there is a caveat here, more on this later.
There are two ways to do this, eat less or exercise more. This is the traditional approach to weight loss.
To discover how to put your body into calorific deficit, you need to know your BMR (Basal Metabolic Rate). This is simply your resting metabolic rate. In other words, the amount of energy, in calories, that you burn each day by just doing your normal daily activities, not including things like sport.
Here is a handy BMR calculator to help you easily find out your BMR. Using myself as an example, I input my height at 169cms, weight of 54kgs, age of 63 and gender, the result is a BMR of 1222. I can then further calculate my daily calorific intake from food to see if I’m in surplus or deficit.
If I’m in surplus, I have the two choices referred to above, I can eat less or exercise more.
Assuming I choose exercise as my preferred option (or both) and decide to option running as my exercise of choice, I can then easily work out how much running I need to do in order to effect my calorie deficit.
How many calories you will burn running is easily calculated using this great Energy Burned Calculator from Bupa. Using myself as an example again, I can see that a 30-minute run will burn around 195 calories.
It’s not hard to see that running is an excellent way to burn calories and drop fat. All it takes is a couple of minutes to calculate a few metrics, then you will have the knowledge you need to see how running can change your body.
And now about that caveat.
The above method is successful in most cases where the runner mostly consumes a Western style diet. However, another way to achieve and maintain your desired weight is with the diet itself.
Carbohydrates from Western style food are highly processed and not appropriate for anyone, especially people who exercise. The trick is to eat a ‘Real Food’ diet or a Keto diet. In fact, these should not be referred to as diets but as lifestyles.
This is a huge subject, but an extremely important one for people not only seeking to lose or maintain weight, but who want to live their most healthy lives. If you would like to know more about this, you can refer to The Natural Nutritionist for the latest information including recipes, I highly recommend this resource.
Weight loss is probably one of the most sought-after ways of how running can change your body.
Running Can Improve Your Cardiovascular Health.
Running changes the very centre of your cardiovascular system, the heart….for the better.
Numerous studies have revealed that runners, particularly long-distance runners, have bigger hearts. The heart is a muscle after all, and like all muscles, the more you exercise it, the bigger it can grow. In fact, some endurance runners have been shown to have hearts 50% bigger than normal.
Not all of us are going to be hardcore endurance runners, but even for the recreational runner doing 5k three times a week, the benefits for the heart and overall cardiovascular system is well proven.
Benefits of Running on the Heart.
- Strengthens the heart.
- Lowers resting heart rates.
- Reduces bad cholesterol in the blood.
- Lowers blood pressure.
- Promotes larger, thicker left ventricles, which allows for greater blood flow.
- Decreases the risk of cardiovascular death by up to 58% over non-runners.
- Can add years to your life-span
Negatives of Running on the Heart.
- Extreme endurance running may thicken heart tissue, resulting in fibrosis or scarring.
- People with pre-existing or undiagnosed genetic heart disease, are at risk of heart failure.
- The science is still out on this one, but the hearts of those runners at the extreme edge of distances covered each week, may develop atherosclerosis, an accumulation of calcium-rich plaque in the heart arteries. Also a possibility, is the development of arrhythmia or abnormal heart rhythm.
Thinking about how running can change your body in terms of your heart, for the vast majority of runners, it’s good news, there are numerous heart health benefits. Once again, though, listen to your body and seek immediate medical advice if something doesn’t feel right.
Running May Shrink Your Boobs and Arms.
Does Running Decrease Breast Size?
If you are running for weight loss and are in a calorie deficit most days, then the answer is possibly. In this scenario, you are losing fat in most areas of the body, and the breasts are no different.
There are two main tissue types that make up the breasts, epithelial and fatty. The composition of these tissue types will differ from woman to woman. If you have a larger proportion of epithelial (breast-feeding) tissue, and less fatty tissue, you may not notice any change at all. Conversely, if you have more of the fatty tissue type, you may experience a more pronounced reduction in breast size.
If you are running for fitness and are not focusing on weight loss, you may not notice any change in breast size at all, since you are probably replacing the calories lost when running with your diet.
Did you know… Running may reduce the risk of breast cancer. Breast size concerns aside, either way, one of the most important benefits of running, and exercise in general, is the possible reduction in the risk of breast cancer. For more in depth information on this, here is a very detailed article from ScienceNordic which explains how this happens, definitely a must-read for all women and their partners.
Supporting the breasts with a properly fitting sports bra is essential for women runners. Ligament stretching and tearing are possible risks associated with the constant and exaggerated movement of the breasts during running.
Does Running Reduce the Size of Your Arms?
You’ve put a lot of work into those shapely biceps and triceps, right? You don’t want to lose them by taking up running. So, will running reduce the size of your arm muscles?
As previously stated, running is cardio, and lots of cardio can burn off body fat. If you are running to lose weight, fat will come off all over the body, including your arms.
So in this case, running may help you to tone up your arms. Removing some fat may even expose those shapely guns that were hiding in there.
For the girls and boys who workout with weights, and have built up some nice arm muscles, you don’t want to do anything that will negatively impact muscle size.
If you drop weight training and switch to running, you will likely lose some arm muscle mass. Running works the legs but not the arms, and as we all know, to maintain or build muscle mass, you need to regularly work those muscles. Your leg muscles will change according to the type of running you do, but to maintain your arm mass, you will still need to hit the weights.
Combining running with strength training is always a good idea anyway, and has a number of benefits for runners. Stronger muscles will build endurance and reduce the risk of injury. Having strong muscles can also assist in reducing stress on your joints as you run.
Shrinking arms and boobs may be one of the least desirable ways of how running can change your body, but as we have illustrated above, there are ways to mitigate this change.
Running Can Give You Greater Core Strength.
Ever get envious of those guys and gals you see sprinting around town with what seems like zero body fat and beautiful rippled abs? Can running really give you abs like that?
Well, yes and no.
If you’re a long-distance runner, you’re out of luck on the abs building front, but you’ll certainly lose fat in that area. In order to strengthen your core and develop those abs, you need to focus on certain running workouts … sprints and hills.
Maintaining stability and balance during an explosive sprint or hill workout is the job of your core muscles. Next time you are storming up a hill, take notice of your core, you can feel the ab muscles working hard.
We always advocate working different running exercises into your weekly workout regime. So even if you’re a long-distance runner, mixing in some sprint work each week is always a great idea, and, you might even end up with a pretty decent six-pack.
Running Can Help You Sleep Better.
Vigorous exercise of any sort, whether it be running or pumping weights etc, will not only help you fall asleep more quickly, but also give you better quality sleep.
What Happens to Your Body When You Sleep?
During sleep, your body will enter recovery mode. The muscles you have worked out during the day will recover, rebuild and strengthen. This is important as lack of sleep can interfere with the body’s recovery process.
Research has shown that exercise can increase the amount of deep sleep you get, this is when the body and brain get an opportunity to recover and rejuvenate.
When Should You Exercise For Better Sleep?
Think of it this way, would you drink a coffee one or two hours before bed? Probably not, if you want to sleep. It’s the same with running. Aerobic exercise, such as running, causes the body to release endorphins. Just like the caffeine in your coffee, endorphins can cause heightened brain activity, which can take a couple of hours to dissipate.
For optimum sleep quality, try not to exercise within a couple of hours of bedtime.
You can experiment with this to see how your body reacts to the late workout. For some people, the exercise will simply tire them enough to fall asleep regardless, but for most people, running earlier in the day will be more beneficial.
How Much Exercise Should I Do to Get Better Quality Sleep?
Aim for at least 30 minutes of aerobic exercise to induce better quality sleep. At least thirty minutes of running has many other benefits aside from sleep quality, as discussed earlier in this article.
We advocate running three to four times a week, with rest days in between workouts to enable proper recovery. On the days you aren’t running, you should still be doing some other form of mild activity, such as walking.
You may have heard many people advocating attaining 10,000 steps a day as a minimum of daily activity. This is largely an arbitrary number and is not based on science, but it does seem like a good number to aim for as an activity minimum.
Exercising in these ways can make a big difference in your sleep quality.
Wrapping It Up.
Scientists are telling us that humans evolved to run. Natural selection favoured the ability to run as a survival mechanism when we dropped out of the trees and began populating the vast African Savannah.
These days, modern humans, have developed incredible running skills. In terms of endurance and speed, it’s a truly remarkable evolution.
Unfortunately, as our lives have become more comfortable, and we employ our intelligence to invent all kinds of machines and equipment to take away the need for physical exertion, we have become soft and flabby.
The epidemic of obesity is testament to this.
As humans, we need to be physically active, we need to engage in aerobic exercise and stress our muscles with resistance training in order to stay fit and healthy.
Running is one such form of aerobic exercise that can build endurance and cardiovascular fitness.
Running will change your body, no doubt about that, in ways that are predominantly good. We are born to run, everyone should run, the benefits to our health are indisputable, as are the beneficial physical changes to our bodies.
Everyone is different and your runner’s body will depend on the type of running you do, whether you train with weights, your build and of course, your diet.
I hope you enjoyed this look into how running can change your body, I’d love to hear about your experiences, please comment below to share.
Happy running
Steve
This article is for information purposes only and is not a recommendation to act on any of its content. It is always recommended you consult your healthcare practitioner before engaging in any activity that may affect your health.
