Many athletes still feel guilty when they take a day off but taking rest days are just as important as the other 3 disciplines (Swim, Bike & Run) for performing at your highest level.
The body needs to repair & strengthen itself in between workouts & continuous training with no rest days can weaken the athlete & lead to injury, overtraining, illness & lack of motivation mentally as well.
Building recovery time into training is critical, this is the time the body adapts to the stress of training & the real training effects take place. Energy stores are replaced & muscles repair, rebuild & strengthen. Insufficient rest & recovery the body will continue to breakdown.
A coach will incorporate rest & recovery within your training program & these will be in the form of Active Recovery (low intensity exercise the day after a hard workout), Rest Day (a whole day off from exercise), Recovery Week (Reduced volume week after a block of progressive training) These forms of recovery help our bodies adapt & become more efficient, we then add additional stress to continue to make progress – these are the things a coach will make sure your training program covers.
Another very important part of rest & recovery is SLEEP & we need to be getting a minimum of 8 hours sleep a night. Consistently getting less than 8 hours sleep a night can result in changes to hormone levels, particularly those related to stress, muscle recovery & mood. So we get an increased level of cortisol which is the stress hormone & a decrease in growth hormone which we need for muscle recovery & a decrease in glycogen synthesis which is needed for energy therefore your aerobic endurance will decrease and perceived exertion rating will be increased making the workout feel harder. So paying more attention to how much sleep your are getting is very important, try getting yourself off to bed earlier to get the 8 hours your body & mind need & see the difference in your training & daily life.