Dizzy After Exercise? Common Causes and Red Flags

You stand up after a set of floor exercises and the room tilts. Or you finish a run, stop at the front door, and suddenly feel light-headed and need to grab the wall. Feeling dizzy after exercise is unsettling, especially when you have kids to look after and cannot afford to be wobbly. In many cases it has a simple explanation, such as standing up too fast, stopping too suddenly or not having eaten. But dizziness can sometimes point to something that needs a doctor, so it is worth knowing the difference.

Here is what I tell clients in Archway: the common causes, what to do in the moment, how to prevent it, and the red flags.

This is general information, not medical advice. If you are on blood pressure medication, have a heart condition, diabetes or are pregnant, speak to your GP about exercise and dizziness.

Common reasons for feeling dizzy after exercise

1. Stopping suddenly

During exercise, your heart pumps hard and your leg muscles help push blood back up towards it. If you stop dead, especially standing still, blood can briefly pool in your legs, and less reaches your brain for a moment. The result is that light-headed, “need to sit down” feeling. It is why I never let people finish a hard round and just stand still.

2. Standing up too quickly

Going from lying on your back (after sit-ups or glute bridges, say) straight to standing can cause a quick drop in blood pressure. The NHS lists a sudden drop in blood pressure when you stand up as a common cause of dizziness.

3. Dehydration and heat

Sweating, especially in a warm room or on a hot day, reduces your fluid levels. The NHS includes feeling dizzy or light-headed among the symptoms of dehydration.

4. Low blood sugar

Training first thing on an empty stomach, or several hours after your last meal, can leave you shaky, sweaty and dizzy. If you have diabetes, this is especially important to plan for with your GP or diabetes team.

5. Holding your breath

Straining while holding your breath, during heavy lifts or long planks, changes the pressure in your chest and can make you see stars when you let go. Keep breathing steadily.

6. Overdoing it

Working far harder than your current fitness allows, often in a first class or a first session back, can leave you dizzy, sick and wiped out.

7. Medication

Some medicines, including some blood pressure tablets, can make dizziness more likely, particularly after exercise. The NHS mentions side effects of new medicines as a possible cause. Do not stop any medication, but do mention it to your GP or pharmacist.

What to do if you feel dizzy

1. Stop and sit or lie down. The NHS advises lying down until dizziness passes, then getting up slowly. Do not try to finish the set.
2. If you feel faint, lie down and raise your legs on a chair or sofa.
3. Sip water slowly once you feel steady.
4. Have a small snack if you have not eaten for a while.
5. Get up in stages: lying, then sitting for a minute, then standing with something to hold.
6. Do not drive until you feel completely normal.

How to avoid feeling dizzy after exercise

• Cool down properly. Walk slowly for 3 to 5 minutes after the hard part, then stretch. My cool-down stretches after a workout are a good routine to follow.
• Change position slowly. After floor work, roll onto your side, push up to sitting, pause, then stand.
• Drink through the day. Pale yellow urine is a good sign you are drinking enough. See my post on signs of dehydration for more.
• Eat something beforehand. A small snack 30 to 60 minutes before training, like a banana or toast, helps if you are prone to shakiness.
• Breathe. Breathe out on the effort of each rep. Avoid long breath-holds.
• Build up gradually. Your first few weeks should feel challenging but manageable. You should be able to speak in short sentences.
• Keep cool. Light layers, fresh air and avoiding the hottest part of summer days.

Dizziness, blood pressure and exercise

Regular exercise is generally good for blood pressure, and the NHS includes being active as one of the ways to help prevent high blood pressure. But if you already take blood pressure medication, your blood pressure may dip lower after exercise, which can make you light-headed. That does not mean you should stop exercising. It means you should cool down gradually, change position slowly and talk to your GP if it keeps happening. I cover the wider picture in my post on exercise and blood pressure.

Red flags: when dizziness needs medical help

Call 999 if dizziness during or after exercise comes with chest pain, a racing or irregular heartbeat that does not settle, fainting or collapsing, severe breathlessness, or sudden weakness or numbness in the face, arm or leg, slurred speech or confusion.

See your GP, following the NHS dizziness advice, if:

• Dizziness keeps coming back or does not go away.
• You notice changes in your pulse, or you have fainted.
• You also have hearing loss, ringing in your ears, double vision or headaches.
• You get dizzy even with gentle exercise.
• You are worried about it.

If you cannot reach your GP, NHS 111 can help.

Where a bootcamp class fits

A good class should never leave you dizzy and alone. In my sessions I build in a proper warm-up and cool-down, remind people to breathe and stand up slowly after floor work, and give an easier option for every exercise. If you feel unwell at any point, you stop, sit down and I will look after you. Small groups, a maximum of 10 people, make that easy.

FAQs

Is it normal to feel dizzy after exercise?

Occasional, brief light-headedness, especially after stopping suddenly or standing up quickly, is fairly common. Regular dizziness, dizziness with gentle exercise, or dizziness with other symptoms is not normal and should be checked by a GP.

Why do I feel dizzy after a run but not during it?

Often because you stop suddenly at the end. Your leg muscles stop helping to push blood back to your heart, and your blood pressure dips briefly. Walking for a few minutes after a run usually helps.

Can low blood pressure cause dizziness after exercise?

Yes. Blood pressure can dip after exercise, and a quick drop when you stand up is a known cause of dizziness. If it happens often, speak to your GP.

Should I exercise again if I felt dizzy last time?

If it was a one-off with an obvious cause, like skipping lunch on a hot day, it is usually fine to try again more gently. If you do not know why it happened, or it keeps happening, check with your GP first.

Book your first class

If you want to get fitter with someone keeping an eye on you, come along. SYP Bootcamp runs 45-minute small-group classes in an indoor church hall in Archway N19, max 10 people, £15 a class, with options for every level. Book my £15 class or call or WhatsApp me on 07301 512215. If you have a health condition or past injury and want a more careful 1-1 approach, read about my injury-safe personal training in Archway.

About the author

Artem Olekhnovych is a personal trainer in Archway and the founder of SYP Fitness and SYP Bootcamp. He has coached clients in Archway, Highgate and across North London for over 10 years, and runs small-group bootcamp classes for busy mums and dads. Read reviews from his 1-1 clients.