Mark (25) and Paul (24) both play for village side Stokeinteignhead, where Paul skippers the South Devon League side and Mark captains the team in friendly matches.
The 'run out' the brothers want to attempt is the Virgin London Marathon – a 26-mile run round the streets of the capital.
The reason for entering the race is to raise money for Tourettes Action, a cause with a special place in the affections of Stokeinteignhead cricketers.
Clubmate Richard Streather's stepson suffers from the condition and Mark was asked if he could help.
"Richard and his wife Zoe asked me to run for Tourettes Action two years ago – and this time my brother is coming with me," said Mark.
"After a year off I am back again and hoping between us we can raise £3,000.
"I have taken part in three London Marathons before, but this is Paul's first time. Last time I ran it I finished in five hours and 11 seconds.
"The race is just over three months away and we are about to start real training for it."
Mark and Paul are using a charity donation website to help them bring in the money.
To make a donation, look up http://uk.virginmoney giving.com/paulrussell.
The run takes place on Sunday, April 25. The brothers already have pledges totalling £300.