The MEN’S FITNESS Running List of Fitness Terms and What They Mean

The MEN’S FITNESS Running List of Fitness Terms and What They Mean

The world of fitness features an evolving language of medical-sounding terms, scientific jargon, acronyms, and phrases that can mean one thing to runners and another to those who train mostly in a gym.

Here we make sense of it all with the first edition of our running list of fitness terms. Stay tuned for updates.

Abductors and Adductors

Often confused since they sound so much alike, some take to calling them “a-b-ductors” and “a-d-ductors.” Abductors are the outer thigh muscles located on the sides of your hips. Abductors are important for lateral movement and stabilization. Adductors are the muscles located in your inner thigh that pull the legs back toward your body and stabilize the hips and pelvis.

Active-Isolated Stretching (AIS)

Created by Aaron Mattes, it’s a series of movements performed with a rope wrapped around one foot at a time to relax and contract muscles through new ranges of motion. You use the rope to gently assist in pulling the muscle a bit farther than your body would normally allow.


As many reps (or rounds) as possible. Popularized by CrossFit, AMRAP typically refers to completing as many reps/rounds of a circuit in a specified period of time. The more reps—with proper form—the better.


The lifting portion of a resistance exercise when the muscle shortens or contracts. In the case of, say, the bench press, the concentric phase takes place when you press the weight from your chest back to the starting position.


Delayed onset muscle soreness. Soreness or discomfort felt 24 to 72 hours after intense training or unusual (for you) physical activity. DOMS is why the second day after training can be more unpleasant than the first.


The ability to bend at the ankle, moving the front of the foot upward. The ability to dorsiflex, running with your big toe up, allows you to store and release energy more effectively. Your stride’s strike zone is beneath your hip, not out in front of your body, and minimizes the potential for tissue trauma and overuse injuries.


The lowering portion of a resistance exercise, when the muscle lengthens. With the bench press, the eccentric phase happens when you lower the bar from the starting position to your chest.


Every Minute on the Minute. A method of training where you begin a set at the start of a minute, complete it, and rest until the beginning of the next minute. The goal is to develop cardio or muscular endurance while training in as little time as possible. Runners and swimmers have called this interval training for years, though EMOM has become popular in recent years in a gym context.


Connective tissue that envelops the muscles, interacts with joints, and attaches to bones. Fascia holds the body together and gives it structure and shape. Fascia organizes and separates, providing protection and autonomy for individual muscles.


The most immediately available source of stored fuel in the body. Made up of sugars and stored in the liver and muscles, it releases glucose when needed by the cells.


High-Intensity Interval Training. A term considered redundant by some since the alternating work-rest nature of interval training is inherently high intensity, HIIT nonetheless has become the popular expression for bouts of work and rest, usually when running on a track or using cardio equipment.


A contraction in which there is no change in muscle length, such as when you lift a dumbbell to a particular height and hold it there. At that point, the muscle is in isometric contraction.

Kinetic Chain

The combination of the body’s nervous, muscular and skeletal systems and the process through which your body works across all the different joints, using all the muscles to create efficient movement.

Lactate Threshold

The point in working out where the demand for cellular energy (lactate) equals the supply. If athletes can raise their lactate threshold, they can perform high-intensity work for longer periods, up to an hour in the case of elite athletes.

Planes of Motion

The three planes (sagittal, frontal, and transverse) in which the exercise is performed. The sagittal divides the body into right and left halves and covers flexing and extending movements. The transverse divides the body into top and bottom halves and involves rotational movements. Dividing the body in half so that you have a front and a back is the frontal plane.


These are jumping exercises that generate quick powerful movements—up and down, side to side, twisting back and forth—activating your body’s central nervous system, stimulating the fast-twitch muscle fibers so you can generate force quickly and efficiently.


Personal record (or personal best). This evolved from more of a running phrase (i.e. 5K PR) into a CrossFit term for best performance in a WOD (workout of the day) or individual lift. A new best in the bench press, long known as a “max bench,” now is also referred to as a PR.


Short for prehabilitation, this refers to the training and conditioning of oft-injured areas of the body, such as the shoulders and hips, to prevent injuries and surgeries that would require rehabilitation or rehab.


The system of pressure sensors in the joints, muscles, and tendons, which provide the body with information to maintain balance.

Reciprocal Inhibition

The neuromuscular response between opposing muscle groups, especially in relation to how they interact, with one relaxing when the other one fires. For example, when you contract your biceps, your triceps are inhibited.

Relative Power

An athlete’s power-to-weight ratio. If a 200-pound athlete drops to 180 pounds but maintains the same power and strength, his relative power has soared.

Static Stretching

Passively stretching a muscle to the point of tension and holding the stretch for a minimum of 30 seconds.


A set of two exercises performed back-to-back, without any rest time between them. Best used with opposite movements, such as a lower body followed by an upper body, or a pushing exercise followed by a pulling.

V02 (or V02 max)

A measure of the amount of oxygen an athlete can take in and process during training per unit time, typically measured in milliliters of oxygen used per kilogram of body mass per minute. The higher your V02 max, the more effective you’ll be as an endurance athlete. World-class cyclists and distance runners have very high max V02.


Workout of the day, pronounced “wad.” Popularized by CrossFit, WODs can be standardized CrossFit routines—often referred to by female names—or combinations of exercises created by a coach and listed in circuit fashion.


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