Alice Arnold, broadcaster and partner of sports presenter Clare Balding, said Daley's coming out video would help his career.
She told Channel 5 News:
It will make him a better diver, because if you've got that monkey on your back you're worried all the time.
It takes a lot of energy to live a secret life and he doesn't have to live a secret life, and that will improve everything for him and for everyone around him.
Ms Arnold said Daley's move would help other gay athletes.
If you look on social media there is still some very bad attitudes amongst the very young in schools and I think he will help that.
I hope that his coming out will help that a lot.
He needs to talk about it because if he wants to go for a meal in a restaurant with his boyfriend there will be cameramen outside waiting for him, paparazzi waiting for him, hounding him every step that he takes.
Olympic medalist Tom Daley said he was overwhelmed by the positive response he had received from the public, after revealing earlier today that he is in a gay relationship.
Overwhelmed by all the support! Means the world! Thanks so much guys ??????
British Swimming chief executive David Sparks congratulated Tom Daley after he revealed he was in a relationship with a man, saying everyone within British Swimming supports him. In a statement, he said:
Everybody within British Swimming supports Tom and his announcement. It's a very private matter and doesn't change the very positive way in which we will continue to work with Tom.
Tom is one of the world's leading athletes and has achieved success at every level of competition including Olympic bronze and world gold.
I hope the media will give Tom the privacy he deserves to allow him to continue to focus on performance as he continues to be an inspiration and role model to millions around the globe.
Edward Coe, chairman of the ASA Group Board, who was himself named a role model by the lesbian, gay and bisexual charity Stonewall last year, also offered his unequivocal support.
We must support Tom Daley in taking this incredibly courageous step.
To be one of the first Olympic athletes to come out is very brave and will, I hope, be a signal not just to other sports people but to all young people that you can be open about your sexuality, even in a very public environment. I am very proud of Tom.
Celebrities, MPs and sport stars have been tweeting their congratulations to Olympic medalist Tom Daley after he revealed he is gay in an emotional online video.
Of course we support you @tomdaley1994 and we all love you even more for your bravery and honesty. X
Delighted that @tomdaley1994 is happy in his new relationship. Well done for sharing it. Good luck to them both.
Surrey and England wicketkeeper Steven Davies, who became the first professional cricketer to publicly reveal he was gay, has tweeted his support for Tom Daley:
Olympic medalist Tom Daley said he was nervous of the reaction from the public on the news that he is dating a man, but that his family have been incredibly supportive, and that he knows his father would be happy for him.
Daley's father passed away in 2011, just a year before he won bronze at the London 2012 Olympics. He said:
"Dad would have said to me, as long as you are happy, I am happy and right now I could not be happier. My mum has been so supportive."
In an online video posted by Olympic medalist Tom Daley, he described how he is constantly asked about his love life in interviews, but that he was not in any kind of serious relationship until Spring, when he met his boyfriend and his life changed.
Come Spring this year, my life changed, massively, and they made me feel so safe and really happy and everything just feels great, and that someone is a guy.
And it did take me by surprise a bit, it was always in the back of my head that something like that could happen, but it was not until Spring this year, something just clicked.
Of course I still fancy girls, but right now, I am dating a guy and I could not be happier.
He said his closest family and friends have reacted in a loving and supportive way, but that he was nervous about a possible backlash from some people.
Olympic medalist Tom Daley has revealed in an online video he is in a relationship with a man, and "could not be happier."
Tom Daley has been suspended over one of the sites of the Glasgow 2014 Commonwealth Games when he was unveiled as the latest and youngest Official Games Ambassador.
The Olympic bronze medallist joins sport stars including Sir Chris Hoy, Jessica Ennis-Hill and Rebecca Adlington in promoting the Glasgow Games which begin in July.
British diver Tom Daley has been unveiled as the latest and youngest Official Games Ambassador for the Glasgow 2014 Commonwealth Games.
He will undertake his first official visit at an event in the city where he will meet fans later today.
He said: "I’m really looking forward to seeing Glasgow and being part of the countdown to the Commonwealth Games.
"I want as many people as possible to get behind the Games and all the athletes. It’ll be fun but tough. I have great memories of winning Gold in Delhi, so I’m totally focused on training and holding on to my title!"