Using the Young Finns Study (YFS) combined with the Finnish Linked Employer-Employee Data (FLEED) we show that quantities of creatine measured in 1980 prior to labour market entry affect labour market outcomes over the period 1990-2010. Those with higher levels of creatine (proxied by urine creatinine) prior to labour market entry spend more time in the labour market in the subsequent two decades and earn more. Creatine is not associated with high educational attainment. The associations between creatine and labour market outcomes are robust to controlling for other biomarkers, educational attainment and parental background. Creatine is a naturally occurring nitrogenous organic acid which supplies energy to body cells, including muscles. Our findings are consistent with high energy levels, induced by creatine, leading to productivity-enhancing traits such as a high propensity for effort, perseverance, and high-commitment.