Expert Advice On Returning To Exercise After COVID-19

Woman resting during workout
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If you've had COVID-19, and you're not suffering from long-term effects, then you may well be wondering how and when you can get back to your exercise routine. If you were training for a specific event, it can be very frustrating to feel like you’ve lost fitness and you may well be champing at the bit. But, according to specialist Dr Rebecca Robinson, it’s worth easing back into exercise carefully and paying attention to your body’s responses. We spoke to her about the risks involved in doing too much too soon, how to judge your body’s response to cardio and strength training workouts, and how long it may take to regain your former levels of fitness.

About Our Expert
About Our Expert
Dr Rebecca Robinson

Dr Rebecca Robinson is a consultant in sport and exercise medicine at CHHP, a sports and physiotherapy clinic. She specialises in helping elite and recreational athletes return to exercise after injury and illness, including COVID-19, and she runs a long COVID clinic at CHHP. She has been a competitive runner for 20 years.

When is it safe to exercise after COVID?

It depends on what you do and how much you do it. Often people won’t actually know straight away that they’ve got COVID-19. In those cases, they’re not likely to have done a lot of damage. They probably felt sub-optimal when they were training, but once they’ve got a diagnosis, it’s really important to stop. 

For most of 2020, there was very strong advice coming from the respiratory and cardiac consultants, saying stop for 10 days. That’s because there was a lot of concern about the way that COVID might inflame areas around the hearts and lungs. 

Over time the virus has changed. People who have had the vaccine appear to have a better response. We’ve cut that advice down to five days for people who have no symptoms: after five days, if there’s a doctor to help guide you, then you can start to return to exercise, but don’t jump into a heavy workout.

What are the risks if you do too much too soon?

I think the main risks come under what we call under-recovery syndrome. The body can’t really tell the difference between being hit by a hard session and being hit by an infection. If it has to deal with both at the same time, it’s going to be too much. 

If the body is putting all its energy into your high-intensity sessions rather than into recovering, you can end up becoming run down and getting some other kind of illness or even an injury because your body wasn’t quite up to it.

Another risk, which thankfully is very rare in athletes, is inflammation, including myocarditis or pericarditis, which happens to a very small minority. If people had myocarditis [cardiomyopathy due to inflammation of the heart muscle], they would know because it’s chest pain. If anyone’s getting chest pain, even mild chest pain, stop, and see a health professional. Although there’s no hard evidence, cardiologists wonder whether just training through recurrent infections might put strain on the heart.  

If you’ve had COVID mildly or without symptoms at all, is it safe to jump back into your previous exercise regime?

That’s a tricky one, because if someone hasn’t had symptoms, they may have continued training. I think even with mild COVID, we know that the body will have launched those immune responses and put energy into fighting it – it’s been working hard – so I still think it’s worth taking your time to return to exercise. 

If it’s mild, cold-like symptoms and above the neck, without a fever, we are saying to some athletes that after three to five days, you can return to light intensity work – as long as you’re feeling good, and you feel good the next day, and your heart rate is what we would expect it to be. Don’t try to make up missed sessions. Always defer to your coach if you have one, or a sports doctor – refer to them for guidance.

How do you know if you’re ready to get back into exercise after having COVID?

Make sure you have recovered from your symptoms and are back to feeling energetic. For a lot of people that’s around day 10. If you feel exceptionally tired, or more tired than normal then it’s just a case of still nurturing your body, still resting – and that’s a really hard thing for athletes to do. 

Look at your resting heart rate. We want that to be back to normal. If it’s two or three beats higher, then OK. If it’s significantly higher – five to 10 beats higher – then you still need to rest. That might mean an extra week off after symptoms have gone.

Unfortunately around 10-12% are going to develop some form of long COVID, although with vaccines those figures are coming down.  

How should people with symptoms of long COVID approach returning to exercise?

That’s one to be really cautious with. I have worked quite a bit with long COVID patients and mostly you need to stop and rest. For people who love sport, or it’s their job, that’s really hard.

It’s important to see a health practitioner. Consult your GP to make sure it’s not anything else because other things can create fatigue, like low iron or hormonal imbalances. It’s always important to make sure we’re not missing something else.

Quite a lot of people with long COVID have this post-exertional fatigue, so they’ll do their training, and they might feel OK, but the next day they’re floored by it. There has to be a really careful approach with working out what level works for you. That’s where having a coach, or health professional to advise you is ideal.

Some people find exercise other than running or cycling or the gym, like Pilates, yoga and breathwork, is really good. Aspects of your nervous system will respond to breathwork. 

Some people find swimming can be a good way of resetting, because it can be less stressful on the system, and it can help some people whose blood pressure drops a little when they’re exercising after COVID.

What about strength training versus cardio? Is one better than the other when you’re returning to exercise after COVID?

I think it depends on the type because, obviously, resistance exercise can be high-intensity. When you do high reps it’s much like what a sprinter would do, in terms of the aerobic work. 

I don’t see why you shouldn’t do lighter-resistance and bodyweight training, moderating that aerobic intensity. I think both cardio and strength training are good and important in anyone’s schedule, but it’s the intensity that matters. 

If someone is hitting the weights and doing deadlifts and that’s causing fatigue the next day, then it’s time to go back to bodyweight work and range of movement first so that you’re still getting benefits, but the stress of the exercises is reduced.

Is heart rate training a good way to ensure you’re working at a manageable level?

So long as it’s used with care it can be really useful. It helps if you know your normal heart rate before COVID. Of course, that can vary – sometimes women will find that it varies during the month, but if they know what their resting heart rate is and their usual heart rate variability, ideally around training sessions, it’s also useful. 

What I have seen, and this is anecdotal rather than pure science, is that sometimes people will be getting back after COVID and once they get back into their training, they feel good, their resting heart rate is fine, but then the heart rate will spike up quite high. We obviously took that very seriously, but it seems to be the nervous system that’s doing that rather than a heart problem. It’s just about backing off at that stage – it’s not the time to go forging ahead.

How long will it take to return to pre-COVID fitness levels?

It depends on how long people have had out. It’s really important to remember you don’t lose fitness in that first couple of weeks. If you’ve had a regular training regime, you retain that fitness. Most people will peak for an event and taper. And they can taper because in that couple of weeks it won’t be detrimental to their fitness. 

I would take as long as the illness lasted to build back up slowly. Say somebody was asymptomatic by the end of the first week. Keep taking things very easy in the second week, building back up into sessions. In the third week take into account that there might be a day or two to step back. So really we are probably looking at a three-to-four-week process, which may feel like forever for a lot of athletes. 

You also don’t want to be doing a fitness test or a competition after those four weeks. That’s a lot more to ask of the body, and that’s when people tend to underperform. 

Camilla Artault
Content editor

Camilla Artault is a writer and keen runner. She has covered women’s running gear – testing leggings, jackets, running bras, tops and shorts – for Coach since 2018, as well as interviewing experts and writing about a range of health and lifestyle topics.