I keep using terms like “volume” and “straight sets” like everyone already knows what I mean. Some of you do. A lot of you don’t, and you shouldn’t have to stop and Google it every time I toss one of these around in a post.
So here’s the fix: a running glossary, in plain language, that I’ll keep adding to as new terms come up. Whenever I use a term in a future post, I’ll link straight back to its definition here instead of re-explaining it every time.
And if I can figure it out, I’ll put this glossary at the top of my homepage.
Quick note: You may be wondering, Why are you randomly sending this out right now, Wendy?
Very good question! I am working on a post about … drumroll… TRICEPS!… that made me think this glossary was a good idea. That post will be along very shortly (not today, but soon).
GLOSSARY
Circuit
The opposite of straight sets — you move through a series of different exercises back-to-back with little to no rest in between, then rest once you’ve completed the full round, and repeat the whole thing again. Faster, more efficient, and it keeps your heart rate up throughout — but because you’re not fully recovering between moves, you typically can’t lift quite as heavy as you could with straight sets.
Compound Exercise
A movement that works multiple muscle groups at once by moving through more than one joint — a squat, a push-up, a bench press. These are generally your most efficient, highest-payoff moves, which is why most solid programs are built around them.
DOMS (Delayed Onset Muscle Soreness)
That soreness that shows up 24 to 72 hours after a workout, especially after trying something new or pushing harder than usual. It’s normal, it’s not a sign of damage, and it’s not something you should be chasing every session as “proof” the workout worked.
Flexibility
How far a muscle can stretch or lengthen, tested passively — think of someone gently pushing your leg toward your chest while you’re relaxed. It’s about the tissue’s ability to elongate.
Hypertrophy
The technical term for muscle growth — an increase in the size of muscle fibers as a result of training, typically through a combination of mechanical tension, muscle damage, and metabolic stress. When someone says a program is “for hypertrophy,” they mean it’s built to make muscles bigger, as distinct from programs built purely for strength or endurance.
Isolation Exercise
A movement that targets one muscle, working one joint at a time — a triceps pushdown or a bicep curl, for example. Useful for directly building up a specific muscle that a compound lift might only train indirectly.
Mobility
How far a joint can actively move through its own range of motion, under your own control and often under some load — like being able to lift your arm overhead and hold it there with strength, not just have someone stretch you into that position. This is the one that actually matters most for lifting safely and effectively, and it’s the one people tend to confuse with flexibility. You can be flexible and still lack the strength and control to use that range of motion — that’s a mobility gap, not a flexibility one.
Overtraining
What happens when you increase training demand faster than your body can recover from it. More isn’t always better — recovery is part of the plan, not a break from it. (See also: Progressive Overload, below — the two get confused, but one is deliberate and gradual, the other is your body telling you it wasn’t.)
Progressive Overload
The training principle behind all long-term progress: gradually increasing the demand on a muscle over time — more weight, more reps, more sets, or slower tempo — so your body keeps having a reason to adapt. Without it, you plateau, because your body has no incentive to keep changing.
Reps
Short for repetitions. One complete movement of an exercise, start to finish — one push-up, one curl, one squat. When I say “10 reps,” I mean you do that movement 10 times before you stop.
RPE (Rate of Perceived Exertion)
A scale, usually 0-10, for how hard a set actually felt — 10 being “I could not have done another rep,” lower numbers meaning you had more left in the tank. It’s a way to gauge effort and intensity when you’re not chasing a specific weight or percentage, and it’s honestly more useful day-to-day than most numbers on a program.
Sets
A group of reps done back-to-back without stopping. “3 sets of 10 reps” means you do 10 reps, rest, do 10 more, rest, do 10 more. Three total groups.
Straight Sets
The most traditional way to structure a workout: you do all your sets of one exercise, resting fully between each one, before moving on to the next exercise entirely. Skull crushers, rest, skull crushers, rest, skull crushers — then and only then do you move to the next move. This is the format that lets you rest the longest and lift the heaviest with the best form, because nothing else is competing for your energy.
Supersets
A middle ground between straight sets and circuits: pairing two exercises together and doing them back-to-back with no rest, then resting once you’ve done both. Often the two exercises target opposing muscle groups (a bicep curl and a triceps pushdown, for example) so one muscle gets a break while the other is working.
Tempo
The speed at which you perform a rep, often broken into phases — how many seconds you take lowering the weight, whether you pause at the bottom or top, and how quickly you lift it back up. Slowing tempo down (especially on the lowering portion) increases how long the muscle is under tension, which is one of the levers you can pull for more growth without adding weight.
Toning
Here’s the truth about this one: it’s not really a fitness term at all. Muscle either has tone or it doesn’t — there’s no separate “toning” mode that’s different from building muscle and losing fat. When people say they want to “tone up,” what they usually mean is some combination of building a bit of muscle and reducing the fat covering it, so the muscle underneath becomes visible. There’s no special rep range, weight, or workout style that “tones” instead of builds — it’s the same muscle-building process as everything else on this list, just marketed with softer language.
Volume
The total amount of work you’re doing for a muscle group — usually thought of as sets × reps × weight, or more simply, just how many total working sets a muscle gets across a session or a week. More volume generally means more growth stimulus, up to a point — past that point, you’re just accumulating fatigue without extra benefit.
This glossary will keep growing. If there’s a term you keep seeing in my posts (or elsewhere) and want defined here, tell me and I’ll add it.
Stay tuned for triceps time!
Wendy
PS: I am opening up some spots for coaching… online and in-person. Click here for info.