It’s intuitive that getting more sleep at night gives us more energy for exercise during the day. Or that getting more exercise in the day leads to more sleep at night.

A recent Australian study turns those ideas on their head.

Scientists monitored 71,000 people over the course of three years. They used wearable devices to track activity and an under-mattress sensor to get a detailed picture of participants’ sleep patterns.

Their surprising results showed that individuals who slept six hours a night took 339 more steps the next day compared with those who got eight hours of shut-eye. In fact, those who slept seven hours walked 237 more steps compared with those who got that extra hour of rest.

What scientists found was that sleep efficiency is a better predictor of next-day energy levels. The analysis also shows that people who took just over half an hour to fall asleep walked less than those who fell asleep in half that time.

Sleep appears to have a greater impact on next-day activity than activity has on sleep. The study found that people who walked nearly 9,000 steps showed almost no difference in their sleep that night, compared with folks who walked 3,000 fewer steps.

The sweet spot for maximizing next-day energy appeared to be approximately six hours of sleep. It was slightly higher for older adults and slightly lower for younger folks.

It’s essential to note that deliberately aiming for less sleep carries its own health risks. But the study suggests new potential strategies for finding the right balance between sleep and activity. Ultimately, they’re both important.