I can share my personal experience of working my way down from 83kg to 76kg while maintaining (indeed improving) FTP and not losing my punchy power. Iâd previously hit that weight but did it in a way where I lost all of my kick which led to a major drop off in interest in riding my bike.
My basic plan is accumulate a ~2000kJ deficit per day, every day, for as many days as you can string together. I highly recommend using a food tracking app, at least for a few weeks, to dial in your understanding of the energy content in your diet and experiment with substituting in less energy dense foods. You can still have days with some treats or just eating more, but youâre always looking to balance it out with a higher level of activity. If you want a day off the bike, you use different tactics (lots of water, tea, and low energy density foods) to get through it.
If you accumulated exactly 14,000kJ deficit in the course of a week, and all of that was fueled by burning fat reserves, youâd burn 370g of fat per week. In practice I find this method achieves ~500g per week of weight loss, averaged out over a couple of months, and eventually plateaus.
You need to trade-off chasing results and doing very high intensity work, since thatâs damaging and you need to be fueling performance and recovery. Accumulating a massive kJ deficit in this mode will come back to bite you eventually.
Focus on steady lower intensity riding to burn kJ without placing undue stress on your body, up to the top of Z2 in a standard 5 zone model (roughly 75% FTP). Lower intensity is fine, too, it depends on whether you want to generate fitness benefits or just burn kJ to hit your daily deficit. I recommend fueling these rides to avoid a big hunger spike later (which often leads to poor decisions that ruin streaks of good habits!) My suggestion is build an understanding of approximately how many carbs youâre burning on these rides, and aim to eat 50% of what youâre burning. Longer rides (2h+) might need more as that gap between carbs burned and carbs consumed grows bigger.
Have things set up so that you can jump on and ride at short notice and for short durations, as life permits. 30 mins of low intensity here and there wonât do much for fitness, but itâs all kJ burned and can really help in hitting that daily deficit target.
Adding in some functional strength training is a good way to achieve some more kJ burn while not putting all the training stress into your legs, and can help build muscle to raise your base metabolic rate (amount of kJ your body burns every day just to keep things running). Also just good for overall wellbeing, particularly as we get older!
Finally, I personally found that a shift towards fat/protein as my primary energy source for day-to-day life, and carbs only to fuel specific activity, was a game changer. Iâm far from perfect since weâre also trying to feed three kids and donât have time to make special meals for everyone; generally dinner is whatever it is but I can be more selective on my other meals.
