Is a rest day absolutely necessary? How about an "active rest" day, say with Pilates or Core training?
I'm not killing myself at the gym (see schedule below) but I only have one day completely off. The days I do cardio usually consists of anywhere from 20 - 75 minutes of running, biking, or swimming (I'm training for my first triathlon). However, I just recently started adding in some strength training which currently consists of 1 or 2 exercises per body part with 3 sets of 12-15 reps. I plan to add in more slowly over the next month or so. I am mixing up the exercises so that my body doesn't get used to one thing.
My problem is that I have a tendancy to have a rest day and then another and then another until I have a whole of week of having done nothing. So I feel like I should at least put in an appearance at the gym and maybe do some Pilates or Core/Stability training on my rest day. But then is it really a rest day? Is this detrimental to my progress?
Mon - Rest
Tue - Legs, back, biceps, calves, cardio
Wed - Cardio
Thu - Chest, delts, triceps, abs
Fri - Cardio (easy)
Sat - Legs, back biceps, calves, cardio
Sun - Chest, triceps, delts, abs, cardio