The Scot is currently ranked 119 in the world after returning to the tour following hip resurfacing surgery two years ago.
A pelvic muscle injury hampered the 33-year-old at the start of this pandemic-affected season, and his last of seven matches this year was a straight-sets defeat to Fernando Verdasco in Cologne in October.
But Murray says he is still capable of mixing it with the best and that the Olympics Games is one of his priorities for 2021.
"I haven’t forgotten how to play tennis. I know I will perform and win big matches if I can get properly fit and healthy for an extended period of time.
And he's looking forward to being competitive again in Grand Slam tournaments and, of course, Tokyo 2020.
"I would love to compete in the Olympics again. That would be huge for me – in the top few priorities for the year. And I’d love to play at Wimbledon again, same with the Aussie Open, and then, if I’m fit and well, I’d be pumped to go and try and win another medal in Tokyo." - Andy Murray at a photoshoot for his clothing brand.
Murray hopes vaccines will help tour "get back to normality"
The former world number one has been practising almost daily at the National Tennis Centre in Roehampton as he looks to build his strength.
But Murray admits he may not have the court coverage he had at his 2016 peak when he won his second Wimbledon title, Olympic gold and the ATP Tour Finals, and went top of the world rankings for the first time.
He said, "I started practising two weeks ago. I’ve been doing tons of work in the gym, trying to build towards beating all of my personal bests, which has been quite exciting for me. I’m really motivated.
"The only thing that I maybe won’t get to the same level is the speed. But I’m hoping that by improving my strength and my power that that will help me get a little bit faster on the court. There’s no reason I can’t get it back to what it was before. And that wasn’t the case probably in the last year. I feel good."
Murray is hopeful that the recent news concerning COVID vaccines will help the ATP Tour return to something like normal.
"I would hope that all the players would be willing to do that for the good of the sport – providing everything has proved to be safe. From what I’ve been hearing on the TV and on the news, there shouldn’t really be any long-term effects."