How Long Does It Take to Lose Your Fitness?
Just as your fitness improves over time, it declines if you stop training. Significant reductions in your cardiorespiratory fitness, that is VO2max, occur already within 2 to 4 weeks of detraining.
CrossFit Challenges the Athlete’s Ability to Recover
Firstbeat provided real-time training load monitoring for athletes in a national CrossFit competition – the Battle of Jyväskylä – in January 2015 with the Firstbeat Sports Monitor.