I am about to start 4:3 or JUDDD (Johnson's Up Day Down Day). Basically as it says, every other day is a "down day." I have been on various forums and some people eat absolutely nothing on their DD's which I definitely won't be doing! My plan is to have 2x 500 cals, 1x <1200cals and other 4 days normal eating. I am wondering about exercise though. I feel like I may have the energy to do a workout on my Down Day's, but my fear is that I will do the workout and then be starving and over eat.
I usually like to work out 5x a week at the gym but I think I may cut back to 3, and then one day a week go for a gentle run or a long walk or something. Is 3 days enough do you think? + 1 run/long walk/swim? Years ago I'd only workout twice a week at the gym but I started getting to know a lot of people there who would workout 5-7 days and they would make me feel very lazy!! I am going to have sunday as an Up Day to enjoy a good sunday lunch but I don't really want to go to the gym on Sunday's as we keep them as family days.
Also does anyone here do pilates/yoga? I've never done it as I get quite self conscious in group classes but am also thinking of taking up pilates once a week on one of my "down days".
Good decision not to do zero-cal FDs (fast days). You want to lose only fat (and maybe water), not muscle. Scientific studies (Varady et al) show 25% of TDEE on FDs is the optimum for retaining muscle while losing weight.
I do 5:2, but I've done brief periods of ADF, basically JUDDD. I train intensely 5-6 days per week, 60-90 mins and I didn't cut down my training. I do HIIT spin, XFit, lifting. boxing and don't care if it is FD or NFD
Always save some calories to eat after training. Your body needs food for repair and recovery. I split my FD calories into lunch and supper, because I train evenings. If you train mornings, you may be ravenous on FDs
Avoid long steady state cardio on an FD, e.g. running or cycling longer than 90 mins, because you may run out of energy. Do sprint intervals instead. People report problems with long runs the day after fasting too, because their glycogen stores are low. HIIT, lifting, Pilates or yoga all work well for fasters.
Some folk need time to do fasted training; others manage ok from day 1. See what works for you, but you don't have to reduce exercise days if you plan properly.