Shoppers can receive a voucher for every£10 spent at Sainsbury's outlets, with an extra voucher for every£5 of fresh fruit or vegetables purchased. Schools can redeem the vouchers for equipment, days out or sports training for teachers.
The campaign is aimed at promoting forms of exercise not common in the school curriculum. A survey conducted by the retailer found that children aged between 4 and 14 years old do just 25 per cent of the exercise their parents did at the same age.
The study also found that one of the main reasons children do so little exercise is their dissatisfaction with schools' sport regimes.
Sainsbury's nutritionist and child behaviour expert Kate Arthur said: 'In schools, you'll see sporty cliques develop that exclude those who don't have the same skills levels. Less able children disengage from it, stop enjoying it and look for other pastimes to become expert in, such as computer games.'