Glossary: 10 terms we hear in the gym and not everyone understands

10 common gym phrases explained | Grace Brown Fitness London | Photo by  Romain Vignes  on  Unsplash

We use tonnes of technical and not so technical jargon terms at the gym which can cause confusion and miscommunication. This is something we want to avoid since we are dealing with your health, especially with lots of heavy weights and machines around!

I’ve put together a list of 10 terms that I have defined in terms of how I use them and the generally accepted definitions.

What other terms are you not sure about or afraid to ask about?

Let me know in the comments below or shoot me an email at

Look out for more to come!

Activate/Create tension

You’ll hear this all the time. In my mind, to achieve this the first thing that needs to happen is connecting your brain to the muscle you are working in that exercise.

Creating tension or activating refers to engaging that muscle or muscle group either throughout or at certain points in the movement.

I might say “squeeze your shoulder blades together” instead of “activate your trapezius” or in a bridge I might say “squeeze your bum at the top” which is the same as “activate your glutes”.

Most common and very important is when you hear “activate your stomach”. This is crucial in so many movements and often, without it, the movement isn’t as effective, if at all. To activate your stomach or your core, think about pulling your rib cage down and together, pulling all the muscles of your side and stomach in together and back. A posterior tilt is usually an essential accompaniment, depending on the movement (see below).

In the case of muscles like the glutes, this can sometimes be really hard to do and can take some time to get right. You may even be able to activate your left glute and have trouble with your right. A sign that it needs some work!

Concentric load

When you cause tension on the muscle as it shortens eg doing a bicep curl, as you curl up, the bicep is shortening and under tension at the same time. The concentric movement of a bicep curl is when you pull the weight up and it is under eccentric load when you push it back down.

Eccentric Load

This is when your muscle is lengthening while under tension. You’ll see eccentric movements accompanied by slower tempos to accentuate the time under tension. In our bicep example, the eccentric movement is when you’re pushing the weight back down rather than up, creating length but still tension. Another example would be a squat. If you lower yourself down into the squat, your quads are lengthening but under tension. The tempo has a big effect in this movement, as I am sure you have experienced yourself. A slow down, fast up squat feels very different to one just up and down! Eccentric loading can also be referred to as “Negative work” or even “negs”. Your body can also deal with much more weight in an eccentric rather than concentric movement.

Isometric Hold

This time we are creating tension in a static position. An example is an isometric bridge hold where you aren’t doing reps, you are holding the position without moving, creating a lot of tension along the way. The Plank is probably the most common isometric hold that many people have in their programming.

I will often deploy iso holds to help clients achieve the muscle/brain connection mentioned earlier. Isometric holds are a fantastic addition to any program - they usually require no or little equipment and it’s a great way to build base strength, engaging a lot of small muscles as well as big muscles. It is often associated with core work and rehabbing injuries but can be used for many benefits.

Hip Hinge

Think of each joint in your body as a hinge joint, one of the hardest to get right is the hip hinge. Extension and flexion of the knee are pretty standard and easy to understand. It’s the same with the hip but can be harder to do as there are many possible areas of tightness and other joints like to join the party.

Hip hinge exercises are important for strengthening your hips, glutes and lower body in general although quite hard to teach someone to do correctly. The body likes to take short cuts and you’ll often see someone bend through the spine or knees rather than at the hips without realising.

The best example, and a personal favourite is the Romanian Deadlift or RDL. Start with soft knees (see below) and a straight/neutral back (also below) and go through the movement only through the hip joint. You can encourage this by sticking your bum out and backwards as you do the movement and trying to point your coccyx to the sky at the same time. It may feel like an exaggeration but it will help!


Pronounced hai·pur·truh·fee - is defined as “increase in bulk (as by thickening of muscle fibers) without multiplication of parts”* and is often used to describe a way of training that focuses on building muscle. This type of training promotes the breaking down of the muscle in order for it to build back bigger and stronger. You’ll see weight training with 8-12 reps, super setting, heavy to almost failure types of exercises as part of this type of training and it will always be challenging. Which is what prompts the breaking down of the muscle.

Keeping knee/elbow soft

“Soft” means that they are ever so slightly bent and not locked out, it doesn’t mean bent. There’s a difference.

In some movements, it’s important not to let these joints fully straighten or hyperextend. At the fully straightened point you often lose tension on the muscles you are working and it means the load is then taken on by the joint - defeating the purpose of the movement.

Let’s take the Leg press. If you keep slightly soft knees, you create more tension in the muscles around the knee but when your knee is locked out and your leg fully straight, your knee joint is doing most of the work and taking a lot of strain while the muscles are more spectators. For elbows, say in a a lat raise, soft elbows mean the movement will hit the shoulders, with locked elbows and straight arms, the tension won’t reach there.

Many people have hypermobile elbows, for example, so keeping them slightly soft is even more important. You’ll see lots of locked and hyperextended elbows during a downward dog at the yoga studio! Keep them soft.

Neutral Spine

Can also be called “keeping a straight back”. This is essential for your spine health. Keeping your spine in a neutral position during a movement protects your back. It’s so important to learn to keep a neutral spine. It can become difficult to keep a neutral spine during posterior chain exercises or hip hinge exercises and so it’s a good one to keep in mind as you go, as you tire during an exercise.

A neutral spine means that your body’s elements are stacked on top of each other and in alignment. That means you shoulders, stomach and hips are all stacked on top rather than your shoulders slumping forward, your belly out or your hips tilted down. It can sometimes feel a little strange to achieve and, if so, that means the posture needs work. A good rule of thumb is sucking your belly in, tiling your hips up to the front (see below), shoulders down and back, with a little squeeze to the shoulder blades.

There are times when you want to train with a rounded back but they are very particular movements.

Pelvic Tilt

This refers to where the pelvis sits over your legs and can be posterior or anterior.

An Anterior Tilt is something that a lot of people have and should be aware of. This means the hips tilt to the floor and your bum sticks out which pushes your belly out and puts pressure on your lower back. You’ll see lots of people do this on instagram to get that thigh gap look. Both anterior tilt and thigh gaps are not things to aspire to.

Posterior Tilt is when you tilt your hips upwards and you’re tucking your bum in and under your hips. This helps achieve a more neutral spine position and you’ll hear me and a lot of trainers saying this to people all the time, for example, anything that has you lying on your back on the floor, you want your lower back to be in contact with the floor at all times and you achieve this with an activated core and a posterior tilt. Many exercises require this and if you’re not doing this properly you may be missing out on the benefits of the exercise AND hurting your back.

Straight Wrist

A common thing I see in the gym, and I’m guilty of it as well, is holding load through the wrist. Weaker wrists and bad habits all play a part here. For example, in a bench press (or any press), holding the bar with bent or tipped wrists rather than straight wrists or in a TRX or seated row, people sometimes curl their wrists in as they pull. It happens often and is easily done.

As you go heavy, straight wrists becomes more and more crucial. Keep your wrists straight to distribute the load and not put strain on the joints.

If you notice you’re doing this, grab a lighter weight and correct the position. Mostly, just be mindful of it and correct it as you notice yourself doing it and you’ll be well on your way.