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Fitness Definitions

Even long-term exercisers may have misconceptions about exactly what some fitness terms mean. Here are some definition of words and phrases you're likely to encounter:

  • Aerobic/cardiovascular activity. These are exercises that are strenuous enough to temporarily speed up your breathing and heart rate. Running, cycling, walking, swimming, and dancing fall in this category.
  • Maximum Heart Rate is based on the person's age. An estimate of a person's maximum age-related heart rate can be obtained by subtracting the person's age from 220.
  • Flexibility training or stretching. This type of workout enhances the range of motion of joints. Age and inactivity tend to cause muscles, tendons, and ligaments to shorten over time. Contrary to popular belief, however, stretching and warming up are not synonymous. In fact, stretching cold muscles and joints can make them prone to injury.
  • Strength, weight, or resistance training. This type of exercise is aimed at improving the strength and function of muscles. Specific exercises are done to strengthen each muscle group. Weight lifting and exercising with stretchy resistance bands are examples of resistance training activities, as are exercises like pushups in which you work against the weight of your own body.
  • Set. Usually used in discussing strength training exercises, this term refers to repeating the same exercise a certain number of times. For instance, a weight lifter may do 10 biceps curls, rest for a few moments, then perform another "set" of 10 more biceps curls.
  • Repetition or "rep." This refers to the number of times you perform an exercise during a set. For example, the weight lifter mentioned above performed 10 reps of the bicep curl exercise in each set.
  • Warm up. This is the act of preparing your body for the stress of exercise. The body can be warmed up with light intensity aerobic movements like walking slowly. These movements increase blood flow, which in turn heats up muscles and joints. "Think of it as a lube job for the body," Bryant explains. At the end of your warm-up, it's a good idea to do a little light stretching.
  • Cooldown. This is the less-strenuous exercise you do to cool your body down after the more intense part of your workout. For example, after a walk on a treadmill, you might walk at a reduced speed and incline for several minutes until your breathing and heart rate slow down. Stretching is often part of a cooldown.

Sample Workouts for Beginners

Before beginning any fitness routine, it's important to warm up, then do some light stretching. Save the bulk of the stretching for after the workout.

Running, walking, gardening – it’s all good. Regardless of what you do, regular exercise and physical activity is the path to health and well-being. Exercise burns fat, builds muscle, lowers cholesterol, eases stress and anxiety, lets us sleep restfully. In this guide, we match resources to your exercise needs -- at every fitness level.

Exercise Benefits

Your heart, your brain – your entire body – benefits from exercise. In this chapter, we’ll bust the exercise myths that hold you back and help you set goals.

The Basics The Basics Exercise Program: The Absolute Beginner’s Guide

There’s no need for a grueling gym workout. Learn the benefits of dancing, gardening, and more.

Your Exercise Routine: How Much Is Enough?

Health experts advise 30-90 minutes exercise daily. Is that realistic for you? Find out if 30 is enough for you.

Stretching and Flexibility

Stretching a muscle to the full extent of your ability and holding it for 15-30 seconds is what's called a static stretch, and there's no harm in stretching that way as long you don't stretch until it hurts. But studies suggest a dynamic stretch is just as effective and sometimes better, especially before your workout.

Your Body Your Body 7 Benefits of Exercise

Sure, exercise makes you sweat. But working out is worth the effort. Here are seven good reasons to just do it. Click here to get started.

Tool: BMI Calculator: Are You Overweight?

With this quick tool, you get a body mass index (BMI) number – an indicator of your body fat. Are you overweight? Find out.

Exercise for Healthy Heart

With this quick tool, you get a body mass index (BMI) number – an indicator of your body fat. Are you overweight? Find out.

Your Mind Your Mind Get Regular Exercise for Mental Health

Exercise is about more than keeping in shape. It also can help with your emotional and mental health.

Tips for Success

The path to a regular exercise routine has great rewards as well as roadblocks. We’ll help make it simple and safe – and give you motivation to push on.

Beating the Obstacles Beating the Obstacles 9 Least Effective Exercises Slideshow

Who has time to waste on ineffective, risky exercises? Not you. So ditch these nine moves that may not deliver the results you want -- and may even cause injury.

The Top 6 Exercise Excuses and How to Beat Them

How to overcome your fitness excuses and start exercising.

Winter Workouts

There are plenty of ways to be active in fall and winter, even if the weather turns cold. You can stay in shape and have fun while you're at it.

Hot Weather Workouts

Summer is a great time for being active. Even if you live where it gets hot or humid, there are ways you can stay in shape year-round. But make sure to take precautions when you are active outside.

Avoiding Sports Injuries Avoiding Sports Injuries Sports Injuries A-Z

Learn about different types of sports injuries and treatments.

Sore Muscles? Light Exercise Can Help

If you’re just starting an exercise program, soreness can come even 48 hours later. Learn what’s going on – and what to do about it.

Lactic Acidosis Related to Exercise

Lactic acidosis occurs naturally during vigorous exercise.

Head Injuries: Causes and Treatments

Head injuries are injuries to the scalp, skull, or brain caused by trauma.

Achilles Tendon Injury

Head injuries are injuries to the scalp, skull, or brain caused by trauma.

Knee Ligament Injuries: PCL, LCL, MCL, and ACL Injury

Ligament injuries in the knee - such as an anterior cruciate ligament (ACL) -- are dreaded by professional and amateur athletes alike.

Rotator Cuff Tear

It's one of the darkest fears of pitchers, tennis players, and many other athletes: a rotator cuff tear.

Prevent Muscle Strains

Muscle strain -- or muscle pull or even a muscle tear -- implies damage to a muscle or its attaching tendons.

Workout Injuries: Prevention and Treatment

WebMD takes a look at common workout injuries, how to prevent them, and what to do when workout injuries occur.

Get Lean

You gain flexibility, burn calories, and look sleeker when you’re active and exercising. Ramp things up a notch, and you’ll reap more results. Start here!

Cardio 101 Cardio 101 Cardiovascular Exercise: The Basics

Running, swimming, biking – it’s all good cardio exercise. Add strength training, and voila – you’ve got cut muscles, too.

Fitness & Running: A Beginner’s Guide

We’ll get you off and running with these tips. Get a good pair of running shoes – and prepare to lose weight.

Walking for Exercise: It Does a Body Good

Feel your body wake up -- get happy and healthy by walking.

Swimming Exercise

Learn about the health benefits of swimming.

Yoga and Pilates Yoga and Pilates 15 Pilates Moves Slideshow

Stretch, strengthen, tighten your core body with Pilates. If you crave a leaner look, learn more here.

Related Guide: Yoga: 5 Tips to the Right Yoga Style

Iyengar, Astanga, Bikram – the many yoga styles can be confusing. This article will help you decide which style fits your needs.

Tools to Use Tools to Use Tool: Resting Metabolism Calculator

What’s your metabolism? Use this tool learn your daily calorie burn. You might be surprised.

Tool: Target Heart Rate Calculator

Use this tool to make sure you’re working hard enough – but not too hard -- during exercise.

Video: Get Your Cardio With Elliptical Training

Not sure what “elliptical” is? It’s a great machine for those who want non-impact exercise. Watch this WebMD video to see elliptical in action.

Fitness Gadgets and Workouts A-Z

Review all types of workouts here.

Fitness Gadgets and Workouts A-Z

Do these shoes help you shape up? Health and fitness experts size up toning shoes. 

Get Strong

Build more strength and you’ll lose more weight -- plus you’ll tighten those problem spots, like abs. We’ll show you the ropes.

The Basics The Basics Weight Training Basics

Call it “weight” or “strength” training, it’s just as important as aerobic exercise. Learn more about the importance of muscle.

Calf-Strengthening Exercises

Want great looking calves? Try these safe, simple, and effective exercises for toning and strengthening your calf muscles.


Learn about plyometric exercises. Find out what plyometric training is, benefits, who should and shouldn’t try it, and more.

Upper Body Upper Body Video: Lats Exercises

Get advice from personal trainer Aaron Small, PhD, on the right way to work those lats.

Video: Biceps Exercises

In this part of our series, we get advice from personal trainer Aaron Small, PhD, on the right way to work your biceps.

Video: Triceps Exercises

Get advice from personal trainer Aaron Small, PhD, on the right way to work your triceps.

Video: Chest Exercises

In this part of our series, we get advice from personal trainer Aaron Small, PhD, on the right way to work your chest muscles.

Lower Body Lower Body Video: Calf Exercises

We all have our “problem areas”, are yours generally found below the belt? If so, these lower body exercises from personal trainer Aaron Small, PhD, can help tone and tighten you from your hamstrings to your calves.

Video: Squats

Personal trainer, Matt Minter demonstrates the right way to use a free motion squat machine to strengthen and tone your  lower body muscles.

Butt Exercises Slideshow

If you feel your "rear view" needs a makeover, the right fitness routine can provide a natural lift.

Abs, Abs, Abs Abs, Abs, Abs Pictures of Core Exercises

Want a toned stomach or a winning tennis game? WebMD's pictures show 11 off-balance core exercises to help get you there.

Video: Yoga for Toning Core

These three yoga poses can help you increase tone and flexibility for your entire body.

Fuel Your Body

Forget gimmicky diets with empty promises. For a healthy, trimmer body, get the right fuel – good nutrition, sans junk food or excess food. Build muscle, not fat.

What to Drink When You Exercise

The options include sports drinks, energy drinks, and just regular water.

Good Sources of Protein

Protein can help you shed those unwanted pounds and keep your belly full. But it's important to eat the right amount and the right kind of protein to get the health benefits.

Hydration Drinks

Outdoor activity is a great way to put the fun into fitness -- but it requires paying special attention to hydration.

Hydration Quiz

Find out how much you know about hydration.

Expert Help

We’ve assembled experts to guide the way – personal fitness trainers, exercise physiologists, nutritionists, medical experts, and more. Learn from their wisdom.

The Experts’ Corner The Experts’ Corner 10 Workout Secrets: Expert Exercise Tips

For many of us, it's hard enough just to get up off the couch. So what's the secret of people who have managed to make exercise a way of life?

Resources Resources Health & Fitness: Resources

Get the exercise and fitness resources you are looking for here.

Heart Rate Calculator

Ensure you're exercising hard enough to get a good workout, but not strain your heart.

While you are exercising, you should count between...


Heart Rate Calculator

Ensure you're exercising hard enough to get a good workout, but not strain your heart.

While you are exercising, you should count between...