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 48
Call 999 (911 in the US)
For chest pain that comes on suddenly and doesn't go away, feels tight or like squeezing, spreads to your arms, neck, jaw, stomach or back, or comes with sweating, feeling sick, light-headedness or breathlessness; arm pain that comes on suddenly with pressure, heaviness or squeezing across your chest; severe difficulty breathing, or a chest that feels tight or heavy; someone who faints while exercising; palpitations that don't go away, or come with chest pain, shortness of breath or feeling faint; or a headache that starts suddenly and is extremely painful, especially while lifting or straining. The NHS says a bleed on the brain may be more likely when lifting something heavy. Don't drive yourself to A&E.
Sources 49, 50, 51, 52, 53, 54, 55, 56
A headache with effort
Ask for an urgent GP appointment or get help from NHS 111 for a headache that's triggered or made worse by coughing, sneezing, bending down or exercising.
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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, it locks, gives way or clicks painfully (painless clicking is normal), or it's hot and red and you have a high temperature. NHS inform adds a knee that swells straight after a twisting injury to that list. See a GP if knee pain doesn't improve within a few weeks. In the US, your doctor or urgent care.
Sources 57, 58
Your hip
Call 999 or go to A&E for severe hip pain after a fall or injury, or if you can't walk or put weight on the leg. Ask for an urgent GP appointment or get help from NHS 111 for severe hip pain that started suddenly without an injury, or a hip that's swollen and hot. See a GP if hip pain hasn't improved after 2 weeks of looking after it yourself.
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A fall or a twist
Call 999 or go to A&E if you heard a crack, the joint or limb has changed shape or points at an odd angle, it's numb or tingling, or the skin looks blue or grey or feels cold. Get help from NHS 111 (in the US, urgent care) if it's very painful, very swollen or bruised, very stiff, or you can't put weight on it or walk more than a few steps.
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Back pain
Call 999 or go to A&E: loss of feeling or numbness around the 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.
See a GP if pain spreading down a leg hasn't improved after a few weeks of home treatment, is getting worse or stops your normal activities. Sciatica on both sides, or weakness or numbness in both legs that's severe or getting worse, is a 999 call or a trip to A&E.
Sources 61, 62
Swollen muscles and dark urine
Very sore, swollen, tight muscles and dark urine after an unusually hard or high-rep session need medical help the same day: it could be rhabdomyolysis, as our elbow pain from pull-ups guide explains. Normal soreness peaks a day or two after a new exercise and fades.
A new lump or bulge in your groin or tummy
See a GP if you think you have a hernia, a bulge or lump that may get bigger when you strain and smaller when you lie down. Get help from NHS 111 if you have a hernia and pain in or around it, a bloated tummy, you feel or are sick, you're vomiting blood or your vomit looks like coffee grounds, you're constipated, you have a high temperature or feel hot, cold or shivery, or you've suddenly become confused. Call 999 or go to A&E for a femoral hernia (a small lump at the top of your thigh, in your groin) with very bad tummy pain, sickness, being unable to fart or poo, a high temperature or sudden confusion.
The NHS lists lifting heavy weights among the causes of a femoral hernia. After an inguinal hernia repair, avoid heavy lifting or strenuous activity for at least 4 to 6 weeks.
Sources 63, 64, 65
Before you start
Speak to your GP first if you haven't exercised for some time or have medical conditions or concerns, as the NHS advises. Get advice before hard or straining work if your blood pressure is uncontrolled (140/90 or higher at a clinic, or 135/85 at home), 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.
With controlled high blood pressure, the American Heart Association considers low- to moderate-intensity strength training with proper breathing safe. Breathe out as you lift, as our breathing guide advises.
Sources 66, 67, 48