Taking up running will change your life. I mean it. Running isn’t just a way of exercising, it’s joining a community (and not in a scary religious cult type of way).
Yet the questions most would-be runners want answering are “How running changes your body?” and “What does running do for your body?” Most of it’s good. Really good.
- Running boosts your cardio, helps reduce stress, and lets you sleep well at night.
- Taking up running is good for your fitness and can help you lose weight.
- Expect to lose body fat and develop envious calf muscles.
Some people even think we evolved to run. If you’re body-obsessed, or just trying to get in shape, I’m sure you’ll want a few more details such as will my butt look good, is running the best way to get fit, and is there a typical runner’s body?
✅ Most people start running to lose weight… then hopefully fall in love with running. If you’ve tried running before and failed to make it stick, this guide will change your view of running.
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You Will Lose Body Fat
When people want to know what does running do to your body, often what they have in mind is losing weight. It’s simple really, weight loss is about the balance between calories in versus calories out, and running is a great way to burn calories.
In my view, it’s the BEST! You burn nearly double the number of calories compared with walking. Each mile you run burns around 100 calories. There’s no expensive gym membership, most people can run right from their door and all you really need is a good pair of running shoes. Develop a regular running habit and you will lose weight.
There are a few caveats. Running makes you hungry. Did I say hungry? I meant starving! Forget to refuel after a run and the only thing on your mind will be, “I need to eat NOW”. (Beware of HANGRY runners – they need feeding!)
If you’re running to lose weight, this can be a bit tricky. You don’t want to replace all the calories you’ve just burnt by reaching for a big sugary donut! It might be tempting but you’re going to regret it!
Make sure the food you’re eating fits with your weight loss plans. I find filling up on whole-grain carbohydrates, beans, and lentils with lots of fresh fruit and vegetables works best. Get a healthy snack lined up ready to eat just after your run.
If you’re running to lose weight, don’t aim for perfection overnight. Get used to running first. When you’re two to three weeks in and running is becoming a habit, then it’s time to give your diet an overhaul – one small step at a time. Forget seeking a halo – it’s best not to change everything all in one go.
Age, metabolism, conditions such as hypothyroidism, can all make weight loss difficult. Yet we’re a society that eats too much and moves too little – and for most people, a running lifestyle will help. If you’re struggling to lose weight through running, strength-building exercises and high-intensity interval training (HIIT) will boost your metabolism AND do wonders for your speed. Just don’t do too much too soon if you’re a running newbie.
Your Thighs Will Become Toned
Always wanted to get rid of fat at the top of your thighs? Running is the answer. It’s hard to think of any regular runners who don’t have toned thighs.
Running gives your legs a terrific workout. Run regularly and your thigh fat will be history.
Your Boobs Will Shrink
This is a downside. To be fair, it’s a downside to losing weight full stop. Most women, (and men), will lose weight off their chest when they take up running.
You can still have an attractive cleavage. Just make sure you wear a sports bra even if your breasts are small. No one wants saggy boobs!
It’s not a question of looks. Sports bras are essential for female runners to protect the Cooper’s ligaments that support the breasts from stretching. Run without a sports bra and it hurts – big time.
Reading Tips For How Running Changes Your Body
Full of encouragement, this is the book to get if you think you hate running!
Runner’s World is always a good place to start looking for running advice.
You Will Develop Envious Calf Muscles
Best chat up line ever? Walking around a bookstore in Sydney I was asked “How did you get such great calf muscles? You must be a runner!”
Now my calf muscles have been admired by many, but using it as a chat-up line was a first!
Running will build your calf muscles giving you shapely legs.
There is a downside. You will no longer be able to fit into skinny jeans, skinny boots, or anything that requires stick-thin skinny legs. Will it bother you? I doubt it. You’ll be too busy running…
Your Arms Will Shrink
This is another downside of losing weight. If you’re running intensely, the muscles you’re not using will slim down. That means no more arm muscles.
There is a way to prevent weedy arms. Combine running with yoga or any other weight-bearing exercise that gives your arms a good workout.
You Will Have The Best Butt Ever
Running doesn’t just tone your legs, it tones everything below the waist. Think stomach muscles of steel and a butt to die for.
When you run you’re really working your gluteal muscles. That means an envious butt without having to hit the gym.
You’ll Sleep Better
Physical exercise increases the amount of time in deep sleep and can help with insomnia. The only proviso is to avoid intense activity in the hours before bedtime.
(No cramming in a run late at night because you forgot to go earlier – set your alarm for an early morning run instead).
Run earlier in the day and feel the benefits when it’s time to get some shut-eye. Sleep soundly and awaken refreshed.
You’ll Feel Terrific
Running just makes you feel great. It gives you energy and builds confidence making you more outgoing. However, when it comes to “How running changes your body” it’s about more than just the physical side.
It’s a wonderful way of making friends and you’ll find yourself enjoying your journey towards becoming a fitter, healthier person.
Being able to move better, run to catch a bus, get the maximum use out of your body, just makes you feel terrific.
You’ll Stop Overthinking Everything
The runner’s high isn’t a myth. Running releases endorphins creating a natural high. This way you get to feel good without any side effects.
It could be the endorphins or just the benefits of exercise, but running creates positive outlooks, helps you stop overthinking and sweating the small stuff. Life’s just better when you’re running regularly.
What Does Running Do To Your Body?
If you’re squeamish, look away now. Personally, I start to feel a little faint whenever I read about heart rates and circulation, but I’ll give it a go just for you.
Let’s talk biology. What exactly is running doing to your body?
When You First Start Running
Initially, you’re going to be out of breath and your heart rate shoots up. You’re breathing oxygen into your lungs and your heart is pumping oxygenated blood into your muscles.
You won’t feel great and your stomach can feel a bit weird. It’s busy breaking down energy causing muscle cells to release gas.
Your muscles will start using Adenosine Triphosphate (ATP) for energy. This is an organic compound that provides energy for cells. It’s stored in glycogen within your muscles and your blood, but we only store small amounts in our bodies. As you start to run your body creates more.
This Needs More Oxygen
To create ATP your body needs more oxygen. That’s why you start breathing harder and faster. Your body diverts blood away from anything that’s non-essential, such as your digestion. It’s a reason it’s hard to eat and run.
You’re burning calories, lactic acid builds up in your muscles and your core body temperature rises. That red face occurs as blood is diverted nearer to the skin to be cooled and you’re sweating profusely to try and cool down.
As You Continue Running
If you’re in shape, you’ll breathe, sweat, and convert glucose to ATP. Your body settles into a comfortable cycle.
When you’re new to running, your body is less efficient and lactic acid builds up. Running starts to hurt! It’s a good reason to go easy when you start out as a beginner runner.
What Does Running Do For Your Body?
Couch surfers love criticizing runners. Anything to give them an excuse not to get off their butts and get some exercise! But just like most things in life, there isn’t a straightforward answer to “Is running good for you?”
Are we born to run?
Chris McDougall’s Born To Run book exploded onto the running scene in 2009. Telling the tale of the Tarahumara Indians who run down prey barefoot to survive, ultra runners couldn’t get enough of the story.
Suddenly runners weren’t just lycra-clad freaks but people following their natural instincts. A whole new movement of people running barefoot appeared overnight – not often with the best of outcomes with our soft western feet and dirty city streets.
The idea we’re natural runners is convincing. Young children love to run and will happily run around playing all day long. Sitting all day at school, peer pressure, electronic gadgets… all conspire to produce nations of non-runners.
It can help with major depressive disorders.
Running pumps out mood-enhancing endorphins and endocannabinoids. The legendary runner’s high is real.
Take my word for it or try it out for yourself. No matter how hard you find your run, you’re guaranteed to come back feeling better about yourself.
Is running bad for your knees?
Grannies love to tell you “running will damage your knees” but is this true or is it just a myth?
That doesn’t mean you’ll be immune from knee pain. Runner’s knee, patellar tendinitis, or iliotibial band syndrome are common overuse injuries.
Just like any other sport, it’s important to treat your body with respect: build your running miles slowly and avoid muscle imbalance. Regular yoga is a great way to stay injury-free.
Endurance runners have bigger hearts
No this doesn’t mean they’re more likely to remember Valentine’s Day! Endurance runners can have hearts that are 50% bigger than normal. They can also have wider arteries and slower resting heart rates. Is this all sounds good but it’s also possible excessive running thickens the heart tissue, causing fibrosis or scarring.
So what is excessive and is it really a risk? Medical science fully supports moderate exercise. Running just 5 to 10 minutes a day can make a big improvement to your health, reducing your risk of heart disease. It’s the effect of high volume running that’s inconclusive. What about those runners clocking up ultra-marathons and pushing through 40+ mile weeks? At the moment there are no clear answers.
That doesn’t mean it’s bad for you. Running persistently gives you good cardio and it’s encouraged by your doctor, you just need to be aware of the potential risk of overdoing it. It’s always okay to slow down or walk on those steep hills. Just listen to your body.
Is running good for you?
It’s a resounding yes! Any downsides to running come from over-doing it. If you want a great body, enhance your moods, sleep better at night and benefit from good cardiovascular health, lace up some running shoes.
Your Runners Body
There’s no such thing as “a typical runner’s body”. Ignore any comments from gym fans that running will make you look weedy.
Or get the idea that you can’t lose weight from running just because the guys at the back of your local race are carrying some extra pounds.
Two of the most famous runners in the world are Usain Bolt and Mo Farah. Completely different bodies. The former is all muscle to run fast and the latter has his body dialed for maximum efficiency to run a marathon.
For female equivalents compare the Olympic sprinter Tori Bowie and former World Record marathon runner Paula Radcliffe.
Your runner’s body will be dictated by your build, what you eat, and how you train. However, if you want to build muscle, such as a curvaceous butt, work on your hill reps and speed intervals.
If you want to lose weight, balance running with a healthy diet, and avoid eating excess calories.
Hopefully, you’ll learn to love running for more reasons than how you look. Take it from me, the health and social benefits are immense.
I hope this insight into “how running changes your body” will convert you to take up running. It’s been a big part of my life for years and has taken me on all sorts of adventures. I’d love to hear about yours…
Frequently Asked Questions – How Running Changes Your Body
Running changes your body by burning body fat and building muscles. Expect to lose fat at the top of your thighs, build stomach muscles of steel, and a butt to die for the weight. When you run you’re really working your gluteal muscles. That means an envious butt without having to hit the gym. Running increasing your strength and endurance plus interval training can boost your metabolism. You’ll lose weight if you combine running with a calorie-controlled diet.
Running is a great way to burn calories and can help with losing body fat. However, if you’re trying to lose weight, you need to combine running with a healthy eating plan. Running will tone your legs and give you a perfect butt. There’s a good chance your boobs will shrink. Running makes you feel terrific. It’s not just a runner’s high, you feel more energetic, it builds confidence, and makes you more outgoing.
Running is excellent cardio and if you combine running with healthy eating you can achieve a high standard of fitness. But running does neglect some muscle groups, especially your arms, so it’s good to add one or two weekly gym workouts, yoga, or HIIT to your training schedule.
It’s best for most runners to take at least one rest day a week. Beginner runners should run no more than alternate days. Running every day won’t give your body a chance to recover and could lead to injury. Building up to a routine of running just 1 to 2 miles a day is achievable and will have terrific cardio benefits such as a reduced risk of heart disease. Running is a terrific way to get in shape.
Running 2 miles a day will definitely tone your body. For best results combine running with healthy eating. If you’re a beginner runner don’t jump right into running every day. You need rest days for your body to recover and to reduce the risk of injury.
Running is an excellent cardio exercise. The intensity of the exercise can mean you burn more calories per minute compared with walking, cycling on the flat, or swimming. Weight loss happens when you use up more calories than you consume. Running can help you lose weight provided you don’t over-eat after your run. You need a calorie deficit to lose weight and running can be a terrific aid to achieve this.
For real change your running needs to be regular – at least 30 minutes 3 times a week. Suggest also walking/cycling for an extra 2 days a week. With this level of commitment, you will start to notice small changes in 3 to 4 weeks and major changes in 2 to 3 months.
Yes! Running is one of the best ways of burning calories but unless you’re going to run a very high mileage every week, you also need to watch your diet. (Please don’t start running a high mileage overnight, it’s a good way to get injured. Always build up your weekly mileage slowly – no more than 10% increase per week). Running one mile burns around 100 calories so it’s easy to replace those calories with an after-run treat. Find out more in my post Running For Weight Loss Plan.