Pain or Normal Discomfort

Quick Intro

Some discomfort is a normal part of exercise: a burning feeling in a working muscle, heavy breathing during hard effort and a dull ache in the muscles a day or two later. Pain that is sharp, sudden, in a joint, in one specific spot or getting worse as you continue is a reason to stop. Chest pain, unusual breathlessness, dizziness or feeling faint mean stop at once and get checked.

This article describes what normal discomfort feels like, the warning signs and a simple way to judge minor niggles.

Normal Discomfort

These feelings are expected when you work hard:

Burning in the muscle. During a set of Bodyweight Squats or a long Plank, the working muscles can burn and feel heavy. This fades within a minute or two of stopping.
Heavy breathing and a fast heartbeat. During hard aerobic effort, breathing hard is your body supplying more oxygen. It settles within a few minutes of easing off.
Muscle fatigue. Muscles feel tired and slightly shaky at the end of a set or a session.
Next-day soreness. A dull, spread-out ache in the muscles you worked, usually starting the day after new or harder exercise, peaking within about one to three days and fading within about four. It eases as you warm up and move gently.

None of these is a sign of harm. They are signs the muscles and heart are working.

Pain That Means Stop

Stop the exercise if you feel:

Sharp or stabbing pain, especially if it comes on suddenly.
Pain in a joint, such as the knee, shoulder, hip or lower back, as opposed to in the muscle.
Pain in one exact spot that you could point to with a finger.
Pain that gets worse as you continue, instead of staying steady or easing.
A pop, snap or tearing feeling, or sudden weakness.
Pain that changes how you move, making you limp or avoid using a limb.
Numbness, tingling or pain spreading down an arm or leg.

Pain like this may be fine after rest, but it deserves to be taken seriously. Stopping costs you one session. Pushing through an injury can cost weeks.

What to Do After You Stop

Stopping is the first step. Then:

Rest the painful area for the rest of the session, and keep moving other parts gently if that is comfortable.
Note what happened: the exercise, what you felt, where it was and how quickly it came on. This helps if you need to see someone.
Check it the next day. Pain that is clearly easing within a day or two and lets you move normally can usually be eased back into with lighter work.
Get it checked if it is not easing after a few days, if there is swelling, bruising or a joint that feels unstable, or if you cannot put weight on it or use it normally.

When you return, start below the level that caused the problem and build up over a few sessions.

Stop at Once and Get Help

Stop immediately and seek medical attention if you have:

chest pain, pressure or tightness,
unusual breathlessness out of proportion to the effort,
a racing, pounding or irregular heartbeat,
dizziness, light-headedness or feeling faint.

These can be signs of a heart or other medical problem and should not be put down to being unfit.

A Simple Guide for Minor Niggles

Many people have small aches, a stiff knee or a tender shoulder that are not injuries but make them unsure whether to train. A guide adapted from tendon rehabilitation can help:

Mild discomfort is usually fine if it stays mild during the activity.
It should settle by the next morning. If it is back to normal or better the next day, the load was acceptable.
It should not be getting worse week to week. A niggle that is steady or improving is usually fine. One that keeps growing needs attention.

If any of those conditions is not met, reduce the load, change the exercise or rest that area, and see a physiotherapist if it continues. This guide is for minor niggles in people without a diagnosed injury. An injury needs its own plan from a professional.

Ways to Keep Training Around a Niggle

You often do not need to stop exercising altogether:

Train other areas. A sore knee need not stop upper-body work.
Reduce the range or the load. A shallower squat or a lighter weight may be comfortable.
Swap the exercise. If Bodyweight Lunges hurt, a Glute Bridge may not.
Lower the impact. Cycling or swimming instead of running.

FAQ

Is it normal for my muscles to shake during an exercise?

Yes. Shaking near the end of a hard set is a sign of muscle fatigue and is common, especially for beginners.

Should I exercise with next-day soreness?

Usually yes, at a lighter level or by working other muscles. Gentle movement often eases it. If soreness is severe, comes with swelling or makes it hard to move, rest and get it checked.

How do I know if knee pain is serious?

Pain inside the joint, swelling, locking, giving way or pain that gets worse over sessions are reasons to see a physiotherapist or doctor.

Is “no pain, no gain” true?

Effort can feel uncomfortable, but pain is not required for progress. Much good training feels hard without hurting.