Disclaimer: I have done intermittent fasting and prolonged fasting since 2015, and it takes a while before you get accustomed to intermittent fasting along with lifting weights on an empty stomach. There are 5 concepts that I have yet to provide some references to provide some validity to what I’m doing. Regardless, try this at your own risk and I’m not responsible for any adverse reactions that happen in your attempt to try this type of routine and your mileage may vary. I am not a nutritionist or any sort of medical professional, and I perform these custom and innovative fasting cardio-based routines at my own risk. Like any fat loss diet, sleep durability is going to be compromised due to higher cortisol, so being more diligent in diet and sleep hygiene is recommended.
Since late Feb 2026, I’ve made it a goal improve my fitness mainly by getting leaner and improving v02 max. From late Feb to April 20th, I managed to lose 3-4 lbs of body fat and increase my v02 max by almost 2 points. It’s good, but not fast enough since I was still at 18.8% body fat, confirmed by DEXA scan taken on April 20th. I decided to take the DEXA scan with the initial plan to do rolling 36-hour fasts for a month to see if I can theoretically lose an average 1.75 pounds of body fat a week. But that plan changed at only after the 2nd day due to noticing that I didn’t lose much body fat overnight according to the HUME fat loss at-home bod pod. It said that I only lost .1 pound when it was supposed to be .4 pounds of subcutaneous fat. This could have been due to me taking ‘zero calorie’ Powerade as a chaser for my electrolyte intake (salt, potassium, and magnesium) to sustain the water fast or taking a CBN/CBD gummy at night which had 4 grams of carbs. The Powerade has about 2 grams per bottle and took 2 of them. There is a possibility that 1-2 grams of carbs is enough to temporarily spike the insulin for a few hours above the threshold where hormone-sensitive lipase is either enabled or inhibited to burn body fat due to ‘high enough’ insulin levels. Regardless, I felt like this wasn’t sustainable and had to change back to the only way that I have successfully lost body fat without too much rebound, which is intermittent fasted cardio.
I unfortunately didn’t think to take a before picture with a waist measurement, but I do have a pic on March 30th with pretty much the same waist size of 34″ (33.2-33.5 pounds of fat). I’m going to provide a 3 pics below with this 34″ along with my estimated index card chart of waist size and body fat mass based on past DEXA scans, and the DEXA scan taken on April to kickstart the journey.
Phase #1 (April 20th to May 20th)
In this 30-day period, I was iterating the right frequency, volume per day, and management of exercises for calorie burn and their intensity in a fasted state. In the last 7-10 days before the scan, I got an iteration that enabled me to lose about 2 pounds a week, which ultimately ended up raising the average fat lost a week to 1.5 pounds of fat a week. I went from 33.5lbs to 27.8lbs in 30 days and gained about 2 pounds of lean body mass, which I’m going to take with a grain of salt even though my lifts did get stronger. In late 2023 and late 2024, I was able to use fasted cardio to get from 15% to 11-12% bf, but the rate was like 1 pound a week. But this time, I was 19% body fat and was not willing to accept only 1 pound a week with a diet break in the 4th week, so I needed something aggressive. Here is a pic of my waist measurement on the day of the DEXA scan on May 21st 2026:
How I increased my fat loss rate from 18.8% bf from previous attempts
The greatest ‘offense’ adjustment was going against a random tip on not fasting everyday to prevent metabolic adaptation. A common fat loss day would be subjecting myself to a 1300 calories quota inside a fasted window typically being 18-20 hours. I would walk to the gym for 2 miles (200 calories), lift (200 calories), walk 2 miles back (200 calories), ride a bike for 12 miles (600 calories), then walk a mile (100 calories) to finish the quota. This would be about 1600 calories fasted burned in a day out of 4000, representing 1 pound of fat, not 3500. This being done about 4 times a week is around 1.5 pounds a week. The highest quota I had was 1700 calories a day to reach .5 pounds of fat in that day.
How I mitigated fat regain from doing fasted cardio
The greatest ‘defense’ is basically not mixing fats and carbs or at least keeping one of them very small. With the HUME fat pad, I was anecdotally able to witness that the Randell cycle is real, meaning that consuming fats and carbs together isn’t a good idea metabolically. My understanding is that when you consume either carbs or fats, the processing of the other gets compromised. The other reason why I stopped consuming fats at night time was because of the idea that fat is insulin-sensitive towards the end of the day and more insulin resisitant earlier in the day. Laymans terms is that fat cells being insulin sensitive is like it being a sponge and not concrete and when there is high insulin, it has a high likelihood on storing fat. Going back to the HUME, there were time where I would have baked potatoes with tuna and drizzled plenty of olive oil to make potatoes more edible, about 2-3 tablespoons of olive oil which is close to 50 grams of fat and every morning, I gained .1 pounds of subcutaneous fat on the next morning which was inherently frustratingand this happened 3 times in a row. Then there were 3 times where I would make rice with a small amount of coconut oil and my fat mass would stay from when I broke the fast to the next morning and that was even when the dried rice was nearly full in the coffee mug which is like 160-180 grams of carbs in a sitting. This was an eye opener, because I have now learned that I have to drastically avoid fat at night time, yet I can be more liberal on the amount of carbs I can eat before sleeping, and weight and waist wouldnt budge, which is a nice benefit and helps with sleep on the stress side of things. Before I forget, I would break my fast with collagen shake and orange juice and some fruits; basically lean protein and carbs, then at least an hour or so later it would be fats, fiber, and fatty protein which would for the most part be eggs, beef, and avocados. This would be a good time to have hard-to-digest foods. It would be 3 times a day since I only had about 5-6 hours to nourish myself. I would intuitively attempt to eat at maintenance. The only dietary quotas were daily protein quota of at least 135-140 grams of protein for muscle preservation, and as a bonus still making strength and muscle gains, and around 100g or more of carbs, basically enough to not have low blood sugar while sleeping. All in all, these adjustments were huge game changers and massively helped prevent slippage, along with more fasted calories burned a week. The amount of carbs and fat consumed per day wasn’t exact, but I noticed that the more fruit I would eat, about 3-4 fruits, in my first meal, the less hungry or hunger headaches I would feel. Realistically, I wouldn’t be completely satidated until maybe after the last meal and that would last for 1-2 hours.
An amazon affiliate link to the HUME product
Phase 2 (May 21st to June 28th)
The plan in this phase was to double down on the rate of 1.5 to ideally 2 pounds a week to see if it was possible past 15% bf and even past 13%. At the first week, the first iteration was to do .4lbs lost (1600 from 1300cal quota with 18-20 hour fast) on Monday(6/1), Tuesday(6/2), Thursday(6/4), Friday(6/5), and Saturday(6/6). I later went back to the 3-day split of -.4lb / -[.4 to .5] / rest day. Twice I had to postpone by fasted cardio day due to 2 important family functions. Just to give a reminder, I have to spent about 4-5 hours to burn a total of 1300 calories combining walking, lifting, and riding the bike before breaking it in the mid to late afternoon. On the day before, my planned DEXA scan, I had my guard down in my diet in a fasted cardio day and went intuitive. As a result of that day, I got insomnia and didn’t sleep at all and the plan was to do a massive fasted cardio day the day before my DEXA scan as a last minute attempt to raise my weekly fat loss average to 1.25 at this point due to post-poning a few too many times. So that day, I lifted in the morning doing push day with no sleep and elbows were aching from pull day that I had no sleep from and ate afterwards. At this point, I had to make the hard choice and not take the DEXA scan since I failed to successfully double down on the success that I had in phase 1.
Here are some images during Phase #2. In reterospect, this was 1.5 pounds of fat in 10 days and not 7 days and definitely not 2 pounds of fat a week. To be fair, it was under 15% body fat.
Things I learned from Phase 2:
- It gets noticeably harder seemingly overnight once I cross the 15% body fat mark. From 15% to 13% seems the same. In this zone, riding the 12 miles on the bike seemed like more work compared to before 15%, so overall less perceived energy for some reason and this was consistent.
- It’s very important to get your protein requirements.
- Other than that, it was pretty much the same.
Aftermath
For July, the plan was to lighten up on the fat loss focus and enjoy summer a bit more. I had done a simple run to check my v02 max expecting a higher v02 max simply due to losing 7 pounds of body fat at this point, and v02 max stayed the same from days before April 20th till June 8th and it was still 49.2. Realizing that, I reluctantly started doing v02 max workouts again and started out with 2 sessions with 2 sets, and I only increased it by +.1 which was confirmed on a 1.5 mile running trial on July 1st. This month of July, I decided to focus on my v02 max improvement and made fat loss secondary until I reached sufficient v02 max levels. I have made surprisingly great strides in my v02 max point beyond belief, which I will touch up more on my next upcoming blog.
Overall, phase 1 was great, tested my limits, and found out ways to both lose it faster and more efficiently, along with habits to help prevent future unwanted fat gain. Phase 2 was not a perfect run, but glad that I was at least able to reach 13% bf. It should be either August or in fall in when I’m going to make fat loss a primary fitness focus on striving for my lifelong goal of reaching 10% body fat. I was sooo close when I was 11.2% bf three years ago which is seen in the DEXA scan image. For now and some of August, my focus will be on maintaining momentum in raising my v02 max which again will be talked about in the next blog.