Martha is taking part in a fitness challenge to support the Bucks Girls Rugby Charity that helps more girls enjoy this brilliant sport.

Donating through JustGiving is simple, fast and totally secure. Your details are safe with JustGiving - they'll never sell them on or send unwanted emails. Once you donate, they'll send your money directly to the charity. So it's the most efficient way to donate - saving time and cutting costs for the charity.