Sport England chief executive Tim Hollingsworth says it is now "more important than ever" to stay active, while following the government's guidance on social distancing.
Because of the coronavirus crisis sports events have been cancelled, forcing people to find different ways to exercise.
"Even if social isolation means being inside - if you feel well, it is easier than ever to get active," he said.
"There are hundreds of options online."
Sport England will launch a national campaign this week to encourage people to stay active in and around their homes and to share their experiences online, using the hashtag #StayInWorkOut.
"We all know that right now what matters most is listening to what the official advice is telling us to do, so we can save lives and protect the NHS," Hollingsworth added.
"What that doesn't mean is that we stop being active, which we believe is now more important than ever.
"From the Prime Minister down, everyone recognises the vital benefit that being active can have. It's not just a means of building and retaining your physical wellbeing, but also crucially it's a way of supporting your mental health and battling back against some of the worst moments of isolation and fear that the coronavirus has instilled in all of us.
"I believe, however, that we will also see a profound change in the relationship in our communities to sport and the need for physical activity, realising more than ever how much it matters to our own sense of wellbeing, and more importantly, how powerful it can be in ensuring the connectivity of communities and in bringing people together."