Keto and exercise

My husband and I recently started the keto diet. Went really good for about 5 weeks and then had a bit of a cheat week. We're back on the wagon now and recently started a kettle bell class. We're only a few days back on the diet & not in ketosis yet. During our class last night we both felt horrible while working out - very dizzy, lightheaded and almost passed out. Just wondering how you experienced keto peeps handle exercise while on the diet? Was this a result of our bodies not being back in ketosis yet and not burning the ketones but rather using up the little bit of glucose that's left in our blood stream? Or should we be doing some kind of 'carb up' with fruit or something before we workout? And if so, how many carbs? Any advice is appreciated!

Replies

  • Carnivor0us
    Carnivor0us Posts: 1,752 Member
    I do a small 'carb-up' before a workout while on keto. An apple or a glass of milk works nicely.
  • hajohn14
    hajohn14 Posts: 3 Member
    How long before a workout would you suggest doing this?
  • Carnivor0us
    Carnivor0us Posts: 1,752 Member
    30 minutes or 20 minutes ahead of time seems to work well for me.
  • hajohn14
    hajohn14 Posts: 3 Member
    Thanks!
  • yarwell
    yarwell Posts: 10,477 Member
    We're only a few days back on the diet & not in ketosis yet. During our class last night we both felt horrible while working out - very dizzy, lightheaded and almost passed out.

    You're short of salt, as you're adapting to keto, low blood pressure due to loss of sodium having cut the carbs. Vigorous exercise is not recommended in the first few days.

    Nothing to do with carbs at all, other than the lack of carb retention of sodium.
  • Once your body is keto adapted (3-5 weeks), you will no longer have those feelings. You still have glucose if needed, while in ketosis. I never suffer on my 2 hr rides on my bike. Burning fat, baby, and a lot of it.
  • albertabeefy
    albertabeefy Posts: 1,169 Member
    Once your body is keto adapted (3-5 weeks), you will no longer have those feelings. You still have glucose if needed, while in ketosis. I never suffer on my 2 hr rides on my bike. Burning fat, baby, and a lot of it.
    This may be true for aerobic activities like cycling, running, elliptical, etc... However kettlebell routines push into the anaerobic. And honestly, ketolysis/lipolysis (utilizing ketones or fatty-acids for cellular respiration) aren't able to fuel anaerobic activity as well as glycolysis (burning glucose).

    As such, if doing something anaerobic - if you don't have much in the way of glycogen reservers, you will do better by eating some carbohydrate prior to the workout. How much depends on both your metabolism AND the intensity/duration of what you're doing. Some may be fine with apple and/or milk ... I tend to need about 40-50g prior to a long/heavy anaerobic session.

    (And yes, if your activity-level and metabolism warrants it you CAN be ketogenic at well-over 50g of carbohydrate, fyi. I sometimes have up to 120g and sometimes as little as 40g ... I test with a meter every day to ensure I stay in ketosis. 120g is fine for a 211lb very-active guy like me, it' wouldn't work for a 150lb sedentary woman, of course.)
  • tennisdude2004
    tennisdude2004 Posts: 5,609 Member
    I find that any activity I do which is about 75% or less output then I have all the energy I need with just ketones. On some weekends I can do a 4 hour hike in the morning on just a cup of coffee.

    However when I do my sprint day exercises or Ju Jitsu, or weights, which are generally high activity I normally have some fruit or a potato about 39 minutes before, just to see me through.

    Good luck.
  • yarwell
    yarwell Posts: 10,477 Member
    I normally have some fruit or a potato about 39 minutes before

    LOL @ "about 39"
  • tennisdude2004
    tennisdude2004 Posts: 5,609 Member
    I normally have some fruit or a potato about 39 minutes before

    LOL @ "about 39"

    Yeah sometimes it's 38 sometimes 40. I'm not stuck to certain routine.:smile:
  • albertabeefy
    albertabeefy Posts: 1,169 Member
    I normally have some fruit or a potato about 39 minutes before

    LOL @ "about 39"

    Yeah sometimes it's 38 sometimes 40. I'm not stuck to certain routine.:smile:
    That's too bad that you're so wishy-washy. You'd have more success if you stayed at precisely 39 :)
  • tennisdude2004
    tennisdude2004 Posts: 5,609 Member
    I normally have some fruit or a potato about 39 minutes before

    LOL @ "about 39"

    Yeah sometimes it's 38 sometimes 40. I'm not stuck to certain routine.:smile:
    That's too bad that you're so wishy-washy. You'd have more success if you stayed at precisely 39 :)

    I have noticed that on the 40 and 38 minute days I don't get as good a result.