Revd Richard Littledale, Minister of Teddington Baptist Church, in West London, will be cycling in aid of Tommy's charity.
He tells Premier he has to see lots of happy and sad things in his job: "As a pastor I get to make all kinds of pastoral visits, many of them very pleasant indeed - I get to be there when a couple are getting married, I get to be there when a new baby is born.
"But perhaps the hardest pastoral visit I've ever made is to a couple who's little baby had been prematurely still-born.
"And the sorrow and the heart-ache in that room was palpable.
"Now Tommy's for many years have been helping coupes in just that situation, both through research and also through counselling.
"I reckon if I'm going to get a stiff back and some sore knees from cycling it's a pretty small price to pay to help them out with the wonderful work they're doing."
He said that he had been training hard on the bike and in the gym between his normal day-to-day pastoral work: "I've done about 700 miles during the training programme.
"I'm as ready as I can be!"
To find out more on donate, please visit Richard's site http://uk.virginmoneygiving.com/fundraiser-web/fundraiser/showFundraiserPage.action?userUrl=Richard100&faId=565353&isTeam=false
#richard100 start in sight pic.twitter.com/Oa1wyzHtrA
— Richard Littledale (@richardlittleda) August 2, 2015
Listen to Premier's Hannah Tooley speak with Revd Richard Littledale here: