The Maidenhead Charity Relay Marathon takes place on Sunday.
A total of 27 teams have entered the race, which sees teams of up to 10 people combine to run a marathon distance around Braywick Park.
Teams can raise money for their chosen charities or just race for fun.
Sarah El-Hawary from Oaken Grove-based Go Figure! Personal Training has entered teams.
She said: "It’s a great opportunity for my clients to get together and do something fun but challenging."
Organiser Purple Patch Running says there is limited space for more teams, but they must enter by Friday.
Entry costs £150 per team. Call Purple Patch Running for more information on 07860 650579 or click here.
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