Silly walks: An urgent practical solution to the inactivity and obesity pandemics

To assess whether the increased energy cost of silly walking (SW) could enhance physical activity, reduce obesity and extend health span, we retrospectively analysed data from 13 healthy adults (seven males, six females; age 22-71 years) who performed three walking trials. Oxygen uptake ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:msub><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> <mml:msub><mml:mi>O</mml:mi> <mml:mn>2</mml:mn></mml:msub> </mml:msub> <mml:annotation>${\dot V_{{{\mathrm{O}}_2}}}$</mml:annotation></mml:semantics> </mml:math> ; in millilitres of O₂ per kilogram per minute), energy expenditure (EE; in kilocalories per minute) and cost per distance (in joules per kilogram per metre) were measured via expired ventilation and gas exchange. Trials included normal walking and two SWs, replicating Monty Python's Michael Palin and John Cleese in the Ministry of Silly Walks sketch (1971). Although both Cleese and Palin SWs evinced greater cost per distance, only the Cleese SW elevated <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:msub><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> <mml:msub><mml:mi>O</mml:mi> <mml:mn>2</mml:mn></mml:msub> </mml:msub> <mml:annotation>${\dot V_{{{\mathrm{O}}_2}}}$</mml:annotation></mml:semantics> </mml:math> compared with normal walking (28 ± 5 vs. 11 ± 3 mL/kg/min; EE, +8.0 ± 2.3 and +5.2 ± 0.8 kcal/min in males and females, respectively). Replacing 1-3 min/day of normal walking with the Cleese SW would require an extra energy expenditure of 12 kcal/day (∼4400 kcal/year), approximately twice the energy equivalent of excess weight gain sufficient to explain the obesity pandemic. The EE associated with SW, requiring no additional physical activity, could potentially eliminate future weight gain and, with a modest extra investment of merely 6-23 min/day, SW could redress the obesity pandemic entirely. Crucially, increasing physical activity by SW is expected to elevate cardiorespiratory fitness ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:msub><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> <mml:mrow><mml:msub><mml:mi>O</mml:mi> <mml:mn>2</mml:mn></mml:msub> <mml:mi>max</mml:mi></mml:mrow> </mml:msub> <mml:annotation>${\dot V_{{{\mathrm{O}}_2}{\mathrm{max}}}}$</mml:annotation></mml:semantics> </mml:math> ), thereby diminishing inactivity-related diseases considerably. Combined with weight loss, relative <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:msub><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> <mml:mrow><mml:msub><mml:mi>O</mml:mi> <mml:mn>2</mml:mn></mml:msub> <mml:mi>max</mml:mi></mml:mrow> </mml:msub> <mml:annotation>${\dot V_{{{\mathrm{O}}_2}{\mathrm{max}}}}$</mml:annotation></mml:semantics> </mml:math> gains could reach ∼90%. If SW had been adopted in the 1970s, the global obesity crisis might have been prevented, or at least greatly attenuated, along with commensurate improvements in fitness and health span.