Gym slang is the shorthand lifters use between sets: chasing gains, hitting a PR, skipping (or never skipping) leg day. Some of it is genuine training jargon, some of it is pure internet joke, and a lot of it is both. This guide explains the words you’ll hear at the gym and in fitness comment sections, with a full entry for each.

Progress and programming

• Gains: progress from training, usually more muscle or strength.
• PR: a personal record, your best lift, rep count or time.
• Bulking: eating extra to build muscle, usually followed by cutting.
• Deload: a planned easy week so your body can recover.
• Leg day: the leg workout, and the day everyone jokes about skipping.

Bodies and looks

• Swole: very muscular. You go to the gym to “get swole.”
• Pump: the tight, swollen feeling in your muscles after a hard set.
• Natty: natural, built without steroids. “Fake natty” is the accusation.
• Mirin: admiring someone’s physique, as in “u mirin brah?”
• Fitspo: fitness inspiration posts and photos.

People and attitude

• Gym rat: someone who practically lives at the gym.
• Beast mode: going all out, with maximum effort.
• Big back: someone who loves to eat, a word bulkers sometimes wear with pride.
• Glow-up: a big transformation, the before-and-after kind.

Where gym talk meets looks culture

Some fitness slang overlaps with online communities focused entirely on appearance. Looksmaxxing is the effort to make yourself as attractive as possible, and to mog someone is to outshine them, usually in looks. They’re common in gym comment sections, but they come with more baggage than “gains” or “PR”: much of that world ranks bodies and faces in ways that can feed insecurity.

Phrases you’ll hear

A few gym catchphrases don’t need entries of their own. “Do you even lift?” is the classic put-down when someone gives fitness advice without looking like they follow it; Know Your Meme traces it to a bodybuilding forum post from 2002. “Never skip leg day” is the warning attached to photos of a huge upper body on skinny legs. And “Light weight, baby!” is a famous shout from bodybuilder Ronnie Coleman’s training videos.

A note on the jargon

Gym slang mixes harmless jokes with real training terms. Words like bulking, cutting and deload describe actual approaches to eating and programming, but an entry here explains what people mean, not what you should do. For a training or nutrition plan, ask a qualified coach, doctor or registered dietitian.

For more, see our Gen Z slang dictionary, internet slang, or the full A–Z index.