Training and recovery
Can You Exercise After a Flu Jab?
Usually, yes. Here is how to train in the first 48 hours, what to do with a sore arm, and how to time your jab around a race.
TL;DR
- Yes, most people can exercise after a flu jab. Gentle movement on the day is usually fine if you feel well.
- The NHS says the most common side effects are mild and get better within 1 to 2 days: a sore arm, a slightly raised temperature and an aching body.
- Keep the first 48 hours easy. If you feel feverish or achy, rest instead of training.
- Sore arm? Train legs, core or cardio and go lighter on pushing, pulling and overhead work with that arm.
- Racing soon? Aim to have your jab at least two weeks before, and avoid the few days right before race day.
1 to 2 days
How long the NHS says common side effects usually take to get better
3
Common side effects the NHS lists: sore arm, slightly raised temperature, aching body
14 days
The NHS says the vaccine usually takes up to this long to work
Yes, you can usually exercise after a flu jab, and most people are fine to walk, jog or do some easy mobility the same day if they feel well. The smart approach is to keep the first day or two light and save hard training until any sore arm, aches or raised temperature have settled.
Flu jab season lands right in the middle of autumn race season, so it can feel like an awkward speed bump in your plan. It does not need to be. This guide covers what the NHS says about side effects, how hard to train in the first 48 hours, how to work around a sore arm, and how to time your jab around a race.
What does the NHS say about flu jab side effects?
According to the NHS, all flu vaccines used for adults are given as an injection, and the most common side effects of the injected flu vaccines are mild and get better within 1 to 2 days. The NHS says they can include:
- pain or soreness where the injection was given
- a slightly raised temperature
- an aching body
The NHS also says more serious side effects, such as a severe allergic reaction, are very rare, and that the person who vaccinates you will be trained to deal with allergic reactions and treat them immediately. It is clear that the injected flu vaccines used in the UK do not contain live flu viruses, so they cannot give you flu.
If you have a high temperature, the NHS says to wait until you are feeling better before having your flu vaccine. So if you already feel feverish on the day, rest and rebook.
The free NHS flu vaccine is offered to people at higher risk of getting seriously ill from flu, including everyone aged 65 or over and people aged 18 to 64 with certain long-term health conditions. If you have a health condition and are not sure whether you are eligible, the NHS says to speak to your GP surgery or specialist.
Can you exercise on the same day as your flu jab?
For most healthy adults, gentle movement on the day of a flu jab is usually fine. A walk, an easy jog, a relaxed bike ride or a stretching session are all sensible choices if you feel normal. Many people also find that moving the arm gently through the day stops it feeling so stiff, although that varies from person to person.
What we would avoid on jab day is your hardest session of the week. You will not know for sure how you will react until later that day or the next morning, and you do not want to find out you have a raised temperature halfway through a set of intervals or a heavy lifting session. Treat jab day like an easy day in your plan. If you need ideas for what that looks like, our guide to active recovery days has plenty of low-effort options.
Should you train hard in the first 48 hours after a flu jab?
There is no single rule that suits everyone, so let how you feel make the call. The NHS says common side effects usually get better within 1 to 2 days, which gives you a sensible window: keep things easy for roughly 48 hours, then build back to normal training once you feel well. Use this table as a rough guide.
| How you feel | What to do with your training |
|---|---|
| Completely normal | Easy to moderate sessions are usually fine. Save intervals, races and max-effort lifts for a day or two. |
| Sore arm, otherwise fine | Train your legs, core or cardio. Go lighter on that arm (more on this below). |
| A bit tired or achy | Walk, stretch or take a rest day. An easy day now beats a poor hard session. |
| Slightly raised temperature or shivery | Rest. Drink plenty, sleep well and skip training until you feel well again. |
| Getting worse, or not settling after a couple of days | Stop training and speak to a pharmacist or GP, or call NHS 111 if you are worried. |
The temperature row is the one to take seriously. Training hard with a raised temperature is widely advised against, whether it comes from a jab or a bug. Our guide to running with a cold covers the same thinking for winter illnesses, and our beginner guide to whether to run when tired or sick walks you through how to make the call on the day.
What should you do about a sore arm and upper-body sessions?
A sore arm is the side effect most people notice. The jab is usually given in the upper arm, so pushing, pulling and lifting overhead with that arm can feel uncomfortable for a day or two. A few simple fixes help:
- Ask about your non-dominant arm. It is worth asking whether you can have the jab in the arm you use less, so everyday life and training feel easier.
- Swap the order of your week. If you had an upper-body strength day planned, move a leg day, run or bike session into its place.
- Go lighter, not heavier. If you do train your upper body, drop the weight, skip heavy overhead pressing on that side, and stop if it starts to hurt more.
- Adjust your HIIT moves. Burpees, push-ups and mountain climbers put weight through your arms. Swap them for squats, step-ups, lunges or fast marching for a day or two.
- Keep it moving gently. Easy shoulder rolls and arm circles through the day are fine for most people, as long as they feel comfortable.
Running is usually fine with a sore arm, although your arm swing might feel a little odd for the first day. If the area becomes very swollen, hot or more painful instead of slowly easing, stop training that arm and speak to a pharmacist or GP.
How should you time a flu jab around a race?
If you have an autumn or winter race booked, a little planning helps. The NHS says the vaccine usually takes up to 14 days to work, so having it at least two weeks before race day gives it time to do its job before the start line. Just as important for your race, you want any side effects long gone before you toe the line.
| When you have your jab | How it fits around a race |
|---|---|
| Three weeks or more before | A great window. The vaccine has time to work and any side effects are long gone before your taper. |
| About two weeks before | Still a good fit. The NHS says the vaccine usually takes up to 14 days to work. |
| Five to seven days before | Usually fine for training, but the vaccine may not have fully kicked in by race day. Keep the next day or two light. |
| One to three days before | Best avoided if you can. Even mild side effects could overlap with race day. |
| A few days after the race | A sensible back-up. Your recovery week is easy anyway, so a sore arm or tiredness matters less. |
Whatever your timing, try to book your jab before an easy day or rest day rather than right before a key session. If your long run is on Sunday, a Friday afternoon jab leaves you less wiggle room than one on Sunday evening. The NHS also says it is best to get vaccinated as soon as you can to protect yourself during winter, so do not push it back for weeks just to protect a training block. If you are unsure how to fit it around a race, a quick chat with your pharmacist or GP can help.
What if you have more than one vaccine on the same day?
The NHS says you can have the flu vaccine at the same time as other vaccines, such as the COVID-19 and shingles vaccines. If you are having more than one, you may end up with one in each arm, so it makes sense to be extra cautious and give yourself an easy day or two before building back up. If you have questions about having vaccines together, ask the person vaccinating you or your pharmacist.
When should you speak to a GP or pharmacist?
Most flu jab side effects are mild and short-lived, but it is worth getting advice if:
- your symptoms are getting worse instead of better, or have not settled after a few days
- you have a high temperature that does not come down
- the area around the injection becomes very swollen, red or hot, or the redness spreads
- you have a long-term health condition and are unsure whether to exercise
- you are not sure whether a symptom is from the jab or something else
Your pharmacist is a good first stop for everyday questions, and you can call NHS 111 if you are worried and not sure what to do. Trouble breathing, or swelling of your face, lips or throat, is an emergency, so call 999 straight away.
How can Edge help you train around your flu jab?
Small speed bumps like a flu jab are where having everything in one plan helps. With Edge Pro, your running, strength, HIIT and mobility sit in one fully personalised plan, so swapping an upper-body session for an easy run or a leg day is simple. You can also message a real coach anytime. Tell them when your jab is booked and they can help you shuffle the week so your hard sessions land on days you feel good.
Edge is free to download, and Edge Pro starts from £19.99 a month with a free 7-day trial. Join 20,000+ members already training with Edge.
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This article is general guidance, not medical advice. If you are new to exercise, returning from injury, pregnant, or managing a health condition, speak to your GP before starting, and see a physio for any niggle that does not settle.
