Browsing for info on the net I found out that stair climbing burns 0.15 kcal per step up, and 0.05 kcal per step down. So today's 532 steps (each way) should have burned an extra 106 kcals - assuming I'd otherwise have been sitting around doing nothing. By the end of next week I hope to be a bit more in condition so I can do 13 "laps" of the "stairway from hell" - a total of 988 steps daily. This should take around 30 mins each lunchtime at work, and burn off 198 extra kcals. As 3,500 kcals/wk equates to 0.5 kg/wk of body fat, this should help me lose an extra .15 kg/wk compared to just dieting.
One thing to note is that even vigorous exercising for the recommended 30 mins/day won't burn off enough calories to lose much weight by itself (although it will help you lose fat and gain muscle, so you look better than just dieting, and will help you get fit). By comparison, eating 500 kcals/day less than your "maintenance" intake should lead to a weight loss of around 0.5 kg/week.
Overall my diet plan is for around 1,800-2,000 kcals/day (with only 5-10% cals from fat). Based on an estimated 2,800 kcals/day for "maintenance" I should lose around 1 kg/week from CRAN (calorie restriction with adequate nutrition) and another .15 kg/week from increased daily activity (exercise). At a rate of -1.15 kg/week in total I should reach my "ideal" weight (based on getting to a BMI of around 22) in 26 weeks - a nice round 6 months. My goal is to get below 70kg before the end of the Australian Financial Year (30th June).
As you lose weight your maintenance calorie requirement drops (also with CRAN your metabolism tends to slow a bit, though this is offset by boosting metabolic rate via exercise). So I'll probably have to add some additional exercise towards the end. Stair climbing is good to start with, as it seems fairly "low impact" if done in a controlled manner (ie. not like Rocky Balboa!), but once I get down to less than 80 kg I'll start to do some rope skipping. Skipping is a good exercise as it can be done indoors, so it's good for home at night, even if it's bad weather outside. Skipping has a METs rating of 12 (METs = metabolic equivalents. One MET is defined as the energy it takes to sit quietly) compared to stair climbing (8.6 METs) and stair descending (2.6 METs). So skipping will burn around twice as many kcals per minute as climbing up and down flights of stairs. So doing 15 minutes skipping each evening in addition to my lunchtime stair exercise would double the amount of calories burnt off by exercising each day.
Once I reach my "ideal" weight I'll ease back on the exercise a bit (to the recommended 30 mins brisk walk a day) so that my weight stabilises while still sticking to the same CRAN diet. Supposedly CRAN has good prospects of helping you reach your optimal lifespan - although starting it seriously at age 45 is not ideal. It would obviously have been better to maintain my ideal weight and stick to it using CRAN throughout my adult life.