Exercise Dictionary: 11 Fitness Terms to Understand

If you've ever worked with a personal trainer, read fitness magazines, or watched workout Youtube videos from home, you may be confused by some of the popular fitness jargon that's bound to come up in conversation.



Between different types of workout protocols, heart rates, metabolic effects, and recovery tips, there are lots to learn for anyone relatively new to the fitness scene.


Not to worry though — below we're breaking down what various fitness acronyms and terms mean, so you can better understand how to choose and schedule workouts that will provide you the most benefits.


Defining Popular Fitness Industry Terms


Here are 11 terms often used in the fitness industry that are helpful to understand:


1. Resting Heart Rate vs. Active Heart Rate


Your heart rate is the number of times your heart beats per minute, which is between 60 and 100 times for most adults. Your resting heart rate is taken when you’re not exercising, such as when sitting or lying. Active people often have a lower resting heart rate (as low as 40) because their heart muscle is in better condition and doesn’t need to work as hard to pump blood.


Your active heart rate indicates how hard your heart is pumping when you're exercising. Your maximum active heart rate can be found by subtracting your age from 220. If you come close to reaching this number when working out, this means you're really pushing yourself.


2. Metabolic Rate


Your basal or resting metabolic rate (or BMR) is the number of calories your body requires to function while you're at rest. This number does not include the calories you use for exercise or other forms of movement, but rather the energy you need to maintain bodily functions.


Your total daily energy expenditure (TDEE) is the number of calories you use each day for bodily functions plus all types of movement and exercise.


About 70% of your TDEE is calories attributed to your basal metabolic rate, while 20% is attributed to exercise/movement, and 10% is attributed to the energy needed to digest the foods you eat.


3. High-Intensity Interval Training (HIIT)


HIIT is a type of workout that involves intervals, meaning you push yourself very hard for a short period of time, then alternate with short periods of rest. The purpose is to get the most cardiovascular benefits possible in the shortest amount of time by exerting maximum energy and effort during your intense intervals.


Some of the reasons that HIIT workouts have become popular include because they aid in stamina and endurance, support a healthy metabolism, build strength, and can be completed in about 20 to 30 minutes total.


You can practice HIIT by running sprints outdoors or on a treadmill, doing the same on a bike, or performing certain types of circuit workouts.


4. Atrophy/Hypertrophy


Hypertrophy is the enlargement of tissues including muscle fibers, which results from the increased size of cells. When you practice strength or resistance training, you'll experience hypertrophy as your muscles get bigger and stronger.


Atrophy is the opposite of hypertrophy; it's the process of body tissues (including muscles) wasting away due to not being used and degeneration of cells that leads to weakness.


5. Isometric exercises


These are exercises that you hold in a static position without moving your joints. Examples include planks or held squats or bridges, which require fixed muscle contractions.


These types of movements can help you to maintain strength and stability. They differ from exercises called isotonic or dynamic exercises where you’re moving through a wider range of motion, like a pushup instead of a held plank or many squats instead of holding one at the bottom.


6. Dynamic Warm-Up


This type of warm-up involves lots of movement rather than holding static stretches. It's done before a workout or athletic competition to help increase blood flow to muscles, enhance flexibility and improve range of motion, all of which can boost performance and protect against injuries.


Some examples of dynamic warm-up exercises include walking lunges, jumping jacks, and arm and leg circles.


7. Compound Exercises


These are exercises that require you to use multiple muscle groups at the same time, including large muscles like your quads, back, shoulders, and core. Some examples of these types of movements include jump squats, overhead presses, and burpees.


When following a circuit-type workout, it's recommended that you include mostly compound exercises because they’re efficient and they can be difficult, which means you're simultaneously getting a cardio workout.


8. Afterburn Effect


Also called "excess post-exercise oxygen consumption," the afterburn effect describes how your body continues to use energy (calories) even once your workout is over to repair your muscles and recover.


Strenuous/high-intensity physical activity increases your muscles' demand for oxygen, carbohydrates, and protein, which help to repair damaged muscle tissue and in the process make you stronger.


For up to 24 hours after a hard workout, you'll benefit from a boost in your metabolism due to your body spending energy on returning you to homeostasis (your pre-workout state).


9. Delayed Onset Muscle Soreness (DOMS)


DOMS describes the soreness, stiffness, and mild pain you experience about one to two days after intense exercise, especially if your body isn't accustomed to the type of movements you were doing. This is a normal phenomenon, although it can feel uncomfortable, and is caused by temporary muscle damage and inflammation that occurs when your muscles are put under stress.


You're most likely to experience peak soreness about 48 hours after a tough workout, which is actually a good sign that you're making improvements once your muscles can heal.


10. Tabata


Tabata is a type of HIIT workout that utilizes compound movements and bodyweight exercises. A typical Tabata workout lasts for about 20 minutes or less, and its intensity can help to build endurance and strength fast.


The structure of this type of workout will usually be: 20 seconds of intense exercise, 10 seconds of rest, repeat at least 8 times or more before resting for longer. You can do this circuit several times, or just once for a super-fast workout.


Some exercises that you can perform during a Tabata workout include various squats, push-ups, burpees, kettlebell swings, lunges, mountain climbers, glute bridges, and others.


11. Plyometrics


This is a type of training that uses explosive movements, speed, and force, typically via exercises like jumping, push-ups, running in place, and kicking.


It's sometimes also called "jump training" and is intended to make your muscles exert maximum force in short intervals of time, which helps you gain strength and power in as little as 10 to 15 minutes when practiced regularly.


Some unique advantages of this type of exercise include the ability to improve control, speed, landing capabilities, stability, anaerobic power, and vertical jump height.