It has been previously shown that exposing Drosophila melanogaster flies to hypergravity (3g or 5g) at a young age for 2 weeks increases male longevity, resistance to heat in both sexes, and delays behavioural ageing, but the causes of these effects are unknown. We hypothesised that these flies could be well protected against free radical attacks and, if this protection persists after removal from hypergravity, can better resist free radicals and finally live longer than flies that have always lived at 1g. If so, the activity of enzymes detoxifying free radicals superoxide dismutase and catalase should be increased in flies that have lived in hypergravity. Results showed that no effect of hypergravity on the activity of these enzymes was observed at 2, 4 or 6 weeks of age. The greater longevity of male flies that have lived in hypergravity at a young age thus cannot be explained by the activity changes of these major antioxidant enzymes.