Stop and get medical help
If you get chest pain or pressure, feel faint or dizzy, are unusually breathless, or your heart races or beats irregularly during exercise, as our plans advise. The American Heart Association says these need immediate medical evaluation.
Source 27
Call 999 (911 in the US)
For chest pain that comes on suddenly and doesn't go away, feels tight or like squeezing, or spreads to your arms, neck or jaw; a sudden, extremely painful headache, for example during a heavy squat (the NHS says a bleed on the brain may be more likely when lifting something heavy); someone who faints while exercising; palpitations that don't go away, or come with chest pain, breathlessness or feeling faint; or signs of a stroke, even if they've stopped. Don't drive yourself to A&E.
Sources 30, 31, 32, 33, 34, 35, 36
Check before you start
If you haven't exercised for some time or have a medical condition, speak to your GP first, as the NHS advises. Get advice before heavy lifting if your blood pressure is uncontrolled, or you have heart disease or chest pain when you're active, a pacemaker or defibrillator, diabetic eye disease, glaucoma, a hernia, recent eye or tummy surgery, or you're pregnant, as our breathing guide lists.
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Your back
Call 999 or go to A&E for loss of feeling or numbness around your genitals or bottom, new trouble peeing or controlling your bladder or bowels, changes in genital sensation during sex or problems with erections or orgasm, or pain, tingling, weakness or numbness in both legs. These are signs of cauda equina syndrome, which needs treating in hospital urgently; don't drive yourself. Back pain with chest pain is also a 999 call.
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Your knee
Get advice from NHS 111 if your knee is very painful, you can't move it or put weight on it, it's badly swollen or has changed shape, or it locks, gives way or clicks painfully; painless clicking is normal. In the US, use urgent care. See a GP if knee pain doesn't improve within a few weeks.
Source 39
A pop at the front of the knee
A pop or tearing feeling at the front of the knee during a heavy squat, then you can't straighten the knee or lift the straight leg, there's a dent above or below the kneecap, or the kneecap sits higher or lower than on the other side: go to A&E or an urgent treatment centre, or get help from NHS 111, the same day. A torn quadriceps or kneecap tendon does best when it's repaired soon, as our knee pain when squatting guide says.
Your hip
Call 999 or go to A&E for severe hip pain after a fall or injury, if you can't walk or put weight on your leg, or for tingling or loss of feeling in your hip or leg after an injury.
Source 40
A new lump or bulge
See a GP if you think you have a hernia. Get help from NHS 111 if you have a hernia and pain in or around it, a bloated tummy, sickness, constipation, a high temperature or sudden confusion. Call 999 or go to A&E for a femoral hernia (a lump at the top of the thigh) with very bad tummy pain, sickness, being unable to fart or poo, a high temperature or sudden confusion.
Sources 41, 42
A dropped bar, plate or dumbbell
Call 999 or go to A&E if you heard a crack, or the injured part has changed shape, points at an odd angle, is numb or tingling, or has turned blue, grey or cold. Get help from NHS 111 if it's very painful, badly swollen or bruised, or you can't put weight on it.
Source 43
Sore, or hurt?
Muscle soreness for a day or two after a new or harder session is common and fades. Sharp pain, or pain that builds during a set or lingers into the next day, isn't: swap to an easier version, and see a clinician if it persists, as our plans advise. The NHS says to stop exercising straight away if you feel any pain or become unwell, and to get help from 111 if symptoms worry you or don't go away.
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