There are a few things in your life that change once you start exercising. You have to learn to fit regular workouts into your schedule. You have to adapt your motivation tactics to find what works to help you. If you’re someone who hasn’t worked out in a while, here’s what you need to know before you get started.

In addition to these lifestyle changes, your body is going to change, too. Your body might not change in the ways you think. You may never, for instance, get a six-pack and you may never reach your “goal weight.”

Focusing on these appearance-based markers of change in your body is actually self-sabotaging. Instead, it may benefit you to focus on the changes that happen in your body that have nothing to do with how you look.

You might start to feel a difference once you start exercising. You might feel a shift in your emotions, for instance, or notice that it doesn’t feel as difficult to walk up a flight of stairs. But what’s actually going on with your body below the surface? Here are a few of the many incredible ways your body changes once you start working out.

You feel sore:

The first time you exercise after not working out for a while, it’s going to leave you feeling really sore. That’s completely normal. Exercise makes little tears in your muscles, which the body then has to repair and rebuild. That’s how muscle growth happens. And at first, it hurts — a lot. But the more you exercise, the better your body gets at exercise recovery.

And as a result, your workouts won’t leave you with as much pain (though that doesn’t mean they won’t still be effective). As your body gets more practice repairing muscles, less actual damage occurs during a workout. So if your first day back at the gym leaves you limping for three days, don’t give up. It gets easier!

Related article: Utilise These 10 Ways To Effectively Combat And Recover From Soreness After A Workout

You have more energy:

This might seem counterintuitive, since you’re expending energy by working out. But exercise has actually been shown to help you feel more energized overall.  Even after just one workout, energy levels are likely to improve.

Related article: 6 Ways On How To Get To The Gym Even When You Have No Energy

You build up muscles:

Yes, you will get “gains,” as the teens say. When you work out, you make tiny tears in your muscle fibers. These tears are then repaired and built upon, resulting in stronger connective tissue and stronger muscles. The diameter of your muscle fibers increases.

Certain types of exercise result in an increase in muscle mass called muscle hypertrophy, which occurs when individual muscle cells expand. This is where the myth women will get “bulky” if they weight train. However, this myth has been widely debunked. No matter in what way your muscles grow, they will start to use up more energy — even when you are not exercising.

Related article: 5 Barbell Exercises for Women To Obtain A Great Start To Your Training And Body Goals

Your brain chemistry changes:

Brain chemistry affects everything from your emotions to your cognitive abilities. When you exercise, your brain chemistry actually changes quite a lot. For one, you release serotonin, a neurotransmitter associated with feelings of well-being and happiness and a lower risk of depression.

Exercise also releases compounds that make it easier for the brain to form neuronal connections, according to research. Other chemical changes occur, as well, some of which are thought to help prevent mental health disorders such as anxiety and depression. Of course, exercise is not a complete replacement for other therapies if someone has anxiety or depression.

Related article: 3 Full Body Exercises To improve Not Only Your Body But Your Concentration And Efficiency

Your hormones are affected:

A good workout can actually cause a shift in the hormones floating around your body. Some of these hormones can make you feel good — the “happy hormones” endorphins and dopamine, for example. Other hormones triggered by exercise, such as irisin, impact your metabolism. Some women experience an increase in testosterone, which helps to build muscle.

And sometimes, the “fight or flight” response is triggered during exercise, resulting in a release of stress hormones such as cortisol. The type of workout is a factor in which hormones are triggered; a gentle yoga flow won’t release as many stress hormones as an intense HIIT workout.

That’s why some people report experiencing problems when they engage in high-intensity exercise too often — too many stress hormones can be caustic.

Related article: Can’t Seem To Tone Up Your Muscles? Here Are The 7 Reasons Why

You grow more mitochondria:

Remember learning about those in high school biology? Mitochondria are known as the “powerhouses” of the cell. They are used to convert compounds derived from food into energy that can then be used by muscles. Exercise, as you might imagine, takes a lot of work. When you work out, your mitochondria need to produce more energy in less time.

When you start to exercise regularly, your body actually starts to grow more mitochondria in your cells. You could actually have as many as 50 percent more mitochondria in your body after just six to eight weeks of regular exercise. This makes your body better at quickly producing energy — and can make exercise feel easier.

Related article: The Time Of The Day When You Burn The Most And Least Calories For Optimal Weight loss

You’ll get better sleep:

If you struggle to get the hours of sleep you need, getting into an exercise routine can help. Exercise helps improve the duration and quality of sleep. The timing of your workout does play a role here.

For some people, working out too close to bedtime can cause a burst of energy that distracts from sleep. However, this isn’t the case for everyone. If you can work out after dark and pass out afterwards without a problem, go for it.

Related article: Start Sleeping Like a Baby With These 8 Secret All-Natural Sleep Aids To Better Your Sleep

Your brain functions better:

It’s smart to exercise — in part because exercise can help you feel smarter. Running is associated with an increase in cell growth in the area of the brain associated with learning and memory. Exercise increases the activity of a compound called brain-derived neurotrophic factor (BDNF).

This compound helps improve brain function and communication between cells. It also may help prevent cognitive decline as you age. That’s one of the many reasons that exercise is the No. 1 recommendation from some doctors for those looking to prevent Alzheimer’s and dementia.

Related article: 9 Exercises That Challenge Your Body and Brain For A Satisfying Body Changing Workout

Your heart rate gets slower:

The more often you do cardiovascular exercise, the better your heart gets at trying to keep up. Your left ventricle actually becomes larger over time. As a result, your heart becomes more efficient at pumping blood through your body, meaning that it has to perform fewer contractions to move the same blood supply.

Therefore, your resting heart rate — the rate your heart beats when you aren’t exercising — decreases. Because your heart beats fewer times, it doesn’t have to undergo as much strain. This effect is part of what makes cardiovascular exercise so good for your heart health in the long-term.

Related article: 4 Exercises To Maintain A Healthy Body And Keep You Looking Fabulous And Strong

Your blood pressure decreases:

A slower heart rate is just one of the many ways that exercise affects your cardiovascular health. Cardio and strength training both affect your blood vessels, as well. Cardio triggers the production of more blood vessels, while strength training makes those blood vessels wider.

Both effects can help to keep blood pressure down in the long term. Of course, your diet has a huge impact on your blood pressure, too, and is still important to keep in mind. Certain foods, could be sending your blood pressure through the roof.