The impact of short-term incentives on physical activity in a UK behavioural incentives programme.

This observational study investigates whether the provision of ongoing short-term-incentives for verified physical activity increases and sustains levels of physical activity. We compared UK members at baseline (years 1 and 2) prior to Vitality's Active Rewards (VAR) intervention commencing (year 3) and follow-up (year 4) for verified, self-reported (encompassing additional physical activities), mortality relative risk and satisfaction with physical activity. Members were categorised into low-active, medium-active and high-active by tertiles of baseline physical activity. Of 11,881 participants, 6477(54.5%) were male, with mean age 39.7(SD 9.8) years. At follow-up, annual active days had increased by 56% overall [60.8(59.7-61.9)-94.8(93.0-96.5)]; 554% in low-active [8.5(8.3-8.7)-47.1(44.7-49.5)]; 205% in medium-active [39.8(39.4-40.2)-81.4(78.7-84.1)] and 17% in high-active members [131.7(129.9-133.5)-153.7(150.7-156.7)] (all  < 0.001). Annual weeks of attaining international physical activity recommendations increased by 19% overall [22.2(42.8%)-26.4(50.8%)] and by 316% for low-active members [4.9(9.5%)-15.5(29.8%)]. Self-reported active minutes/week increased by 45% overall [1423(139.4-145.2)-207.0(201.8-212.3)] and 712% in low-active members [20.1(19.3-21.0)-143.2(134.6-151.9)]. Happiness with exercise levels also increased from 1985(49.4%) to 3414(84.9%) members (all  < 0.001). The relative risk of mortality from a lack of physical activity reduced by 7% for low-active members [from 0.99 to 0.92], 5% for medium-active [0.94-0.89] and 3% for high-active [0.89-0.86]( < 0.001) and by 0.02% for each additional year of age ( = 0.02). This large-scale, real-world, short-term-incentives intervention led to a dramatic increase in physical activity which was sustained for, and still increasing after, two years. If applied at broader level, this approach could considerably aid progress towards WHO targets in its Global Action Plan for Physical Activity.