This past season, WHOOP and Major League Baseball conducted the single largest performance study in professional sports history. Nine organizations were involved, with 230 players from 28 different minor league teams participating.

Among the data recorded were over 4,400 nights of sleep from various players wearing WHOOP straps. What can we do with this information? One of the more useful applications is to look at how travel affects players’ Sleep and Recovery.

For this particular analysis we examined 1,203 days worth of data, 218 involving travel and 985 without. On average, players spent 7.8 hours in bed the night after traveling, but 8.6 hours in bed following non-travel days.

Not only does WHOOP track the time an athlete is in bed, it also automatically detects how much of that time is actually spent sleeping. Players averaged 6.1 hours of sleep per night after traveling, compared to 6.8 when they didn’t travel.

Along with an increase in Sleep on non-travel days, there was also a measurable uptick in players’ WHOOP Recovery following days without travel. Spanning the entire data set, the average Recovery (on a scale from 0 to 100) was 54.0 the day after traveling, but 59.1 on non-travel days.

The chart below represents all recoveries, with the red symbolizing those following travel and the green indicating no travel:


After a night of reduced sleep post-travel, players tended to revert to their average Sleep duration the next day. However, that was not true for their Recoveries. One might think that a night of regular sleep the day after traveling would get players’ bodies back to normal, but Recoveries took roughly two days to return to their pre-travel baselines.

The same can be said for heart rate variability (HRV), which also took an average of two days following travel to reach players’ baseline levels.

What does this mean?

If a baseball team returns from a road trip on Sunday night, its players are not likely to be at their best again until Wednesday. Armed with this knowledge, managers can plan accordingly. Options include things like giving certain guys an extra game off to rest if necessary, or potentially sending upcoming starting pitchers home a day or two early ahead of the team.

The effects of travel we observed in minor league baseball coincide with the findings of a previous WHOOP case study involving travel in the NBA. In each situation, a clear relationship was discovered between travel and Recovery across the board–travel reduces next-day Recovery.

With similar results from both sports, it’s reasonable to consider the possibility that travel has a serious impact on the performance of all athletes.

Visit The Locker tomorrow for Part 2 of our Special Report on the WHOOP MLB Performance Study.

Introduction: WHOOP and MLB Conduct Largest Performance Study Ever in Pro Sports