just want to share a frightening experience, as i decided to do a home workout during a fast. i was like 36 hours into the fast, had an electrolyte drink before the workout and in between sets, but afterwards I was standing up next to the treadmill after a stretching session and lost control of my body. Actually felt my arms getting shutdown (dropped my phone) and then my legs gave up. and then i just hit the ground and everything went black for what i felt was like a few seconds, but the youtube video i was just started watching has finished which is at least 3 minutes.
When i got by I quickly regained power and could just stand up normally. only had both my knees scuffed for hitting the hard concrete floor.
This experience made me wary and afraid actually. i had plenty of electrolytes and stayed hydrated with electrolyte drinks in between sets I measured my blood afterward (within 15 minutes) and it says 4.1 mmol/l glucose and 1.2 mmol ketones. so that’s pretty fine in my books.
it was y plan to do a 7 days fast, but i broke it early after this.
I am now in a pinch:
keep fasting, but don;t workout, or do shortburst (24h) fast with fasted workouts and refeed.
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as for the workout, it wasn’t vey intensive only:
3 rounds farmer walks @ 10 meters singlesideloaded30kg).
4 sets of upper body strength training (bicep curls, pushups and pulldowns)
8 sets of tabata style 24kg kettlebell swings
and ended with
45 minutes of (zone2)jogging @ 5mph in a C25k program
basically a zone2 training for me, “just to stay in shape/prevent muscle loss during fast”-routine. I had long (120h+) fasts with intense workouts (tabata style skipping ropes, tennis for 3 hours) before. body fat+ketones were enough to feed the workouts. Resulting with ketones reaching 4 mmol and glucose dropping to 3 mmol, a bit dizzy afterwards, but never passing out. and during fasts i often do the c25k program. it’s just that week 6 is properly the hardest (running 15 minute with 3 minutes restwalking inbetween set).
so the question is: long fast for weightloss without workouts, or short fast with workout and refeed for muscle/strength building? I’m leaning towards the latter now.
as i’m now at the last day of the week 6 of a c25k program, with 2 weeks left, i want to finish the full program and do a daily zone2 5k run 3 times a week.
40kg of body fat now 35% bodyfat, which i want to reduce to 20% (IE lose 20kg)
I have felt faint while exercising heavily without eating. Not even necessarily during a long fast. I used to be diabetic and I would consider your blood glucose at that time to be too low for intensive exercise.
If your blood pressure drops too low, this can happen. One of the benefits of fasting for someone with hypertension is a normalizing of BP. If you don’t have hypertension, fasting can lower it to the point of making you dizzy or passing out when you stand, sprint, etc.
In the keto circles, some people “carb load” before working out. Basically they treat carbs like a supplement, taking dextrose tablets (nekko wafers candy etc). You could potentially do something similar if you believe the fast is the reason you passed out.
It really depends on your personal goals and beliefs when it comes to fasting. If it’s not “cheating” to you, it might be something worth looking into.
The 45 minutes of jogging sounds like the most difficult part of that to me. I exercise during fasts but usually resistance training with < 10 reps and some jump rope for 2-3 minutes at a time. I do notice my endurance drops. Were you doing your normal electrolyte routine?
I’m currently on Day 3 of my fast.
During the first day, I literally sat at home all day and binged watch TV shows and movies until bed.
Day 2, I managed to do some errands and chores.
Today, I plan to do a long walk with the dog, more errands and study.
Eventually, I’d want to be fat adapted enough to actually work out during these extended fast.
What made you decided to do tabata?
Fasting and strength training don’t work.
THE LAST THING you want to do while not eating food is tear down muscle. Why in the world do people do this? If you are metabolically flexible (e.g. body fat % is normal, healthy body weight range, no symptoms of metabolic disease), then perhaps working out at the end of an 18 hour fast, and then eating well after the workout makes sense.
Muscles are built in the kitchen NOT THE GYM. The gym is where you stress and tear down muscle to stimulate growth, which you do by eating good food.
If you’re not going to eat, light exercise is fine, may even be beneficial. But strength training? Come on.
Unless somehow you think your body can violate the laws of thermodynamics and produce something from nothing, why in the world do think you’re going to build muscle from no food?
PS: Every electrolyte counter acts the other. If you don’t get the balance right you can cause significant alterations in extracellular ion homeostasis.
In other words taking too much can be just as bad if not worse then having too little. When it comes to taking electrolytes small amounts are recommended.
this is a too intensive workout, who gave you the idea to do this? You can moderately run and do light exercises but using 30kg, doing full reps or running for 45 minutes @5mph is reckless beyond belief. You got lucky before that nothing happened, this time it did. Next time you will seriously hurt yourself.