Rest Up, CrossFitters

What are the effects — good or bad — of doing high-intensity CrossFit-style workouts on consecutive days?


The inherent dangers, or lack thereof, of CrossFit-style training have been a hotly debated topic for years. Fortunately, science is starting to join the conversation via research that analyzes CrossFitters’ bodily responses to training.

An intriguing study led by Dr. Ramires Tibana of Catholic University of Brasilia (Brazil) and published in mid-2016 in the journal Frontiers in Physiology, sought to answer one very specific question (paraphrased for simplicity): What are the effects — good or bad — of doing high-intensity CrossFit-style workouts on consecutive days?

It’s a legitimate question, because the traditional CrossFit model calls for three consecutive days of training followed by one rest day, repeated indefinitely. Training frequency obviously varies from one person to another, but the point is, training intensely on consecutive days is common in CrossFit.

In the study, a group of nine male CrossFitters (average age 26) performed two high-intensity WODs spaced 24 hours apart. Both workouts included strength and power exercises as well as gymnastics movements. The difference in the two sessions was the metcon (short for metabolic conditioning) performed at the end. In the first workout, the metcon was 10 minutes of as many rounds as possible of 30 double-unders and 15 power snatches (34 kilograms). The next day, the metcon was 12-minute AMRAPs of rowing 250 meters and 25 “target burpees.”

The results showed that the CrossFitters experienced suppressed immune function from the workouts, evidenced by a reduction in levels of anti-inflammatory cytokines. So does this mean you shouldn’t do CrossFit? No, that wasn’t the conclusion of Dr. Tibana and his team. 

The researchers recommended that CrossFitters either (a) decrease training volume after working out intensely two days in a row or, better yet, (b) space CrossFit-style workouts 48 hours apart instead of 24.

In both cases, we recommend active recovery in the form of a low-impact activity like swimming, biking or yoga in between days of high-intensity training. Giving your body a break from demanding workouts will reduce injury risk and have you feeling fresher for every training session.