Keto and Fueling for Exercise

#1

My doctor prescribed a LCHF diet for me because I was having neurological issues when I worked out. Part way into exercising I would get dizzy, see lights and have loss of vision. Scary! I would stop, eat something with protein and sugar and feel better. I have afib so I spent a few years thinking it was my heart but thanks to blood glucose testing I finally figured out that my levels dropped within mere minutes of the workout beginning.

I’ve been on the Keto Diet for 21 days now (-11 lbs) and tonight is the first time I have ventured onto the treadmill. Of course, nausea decided to fight for a ring side seat but other than that, I was fine. Preworkout blood glucose was 87 and post was 90.

My question is this: How do I prefuel a workout? I plan to ride my mountain bike long distances regularly when Mother Nature stops being rude. What cautions would you give so that I do not push myself out of ketosis? Also, at what point during your exercise do you refuel and with what?

Thanks!

Karen

#2

I’ve been doing my workouts - hikes, mountain bike rides, and indoor climbing sessions - in a fasted state. I stay hydrated, but don’t eat anything while exercising or even immediately afterward. I find it easier to stay alert for the drive home if I continue my fast until I get home.

(Mariah Pleake) #3

I have seen that when I fuel up on a high fat Abd protein meal about 30 minutes to 1 hour before walking that I have a lot more energy and don’t get tired as quick. I do 2 eggs, 4 strips bacon, and about 1/2 an avocado.

(What The Fast?!) #4

I would test different foods for pre-workout - each person is different. What I can tell you for SURE is to take some salt before your workout. When I’m supplementing enough salt, I get dizzy and light-headed during workouts too. When I was doing a lot of fasting, I would take a couple salt pills and it fixed the problem right away. I’m also a cyclist and take them when I ride.

I don’t do well on a ride if I fast beforehand, I try to eat about 45 min before - usually bacon (I can’t have eggs).

(Stacy Blanchard) #5

The Fat-Burning man podcast, as well as others, have many guests on that do all kinds of intense workouts. They have great experience and insight. It might be worth searching some of these out. The 2keto dudes podcast have some answers too-listen to the episode sitting down with Peter Brukner. I’m sure others can suggest more resources. Good luck. :muscle:t5:

#6

Can you sustain an endurance workout in a fasted State?

#7

Thanks. I drink mostly electrolyte water but I will add some salt. Great suggestion.

#8

Thanks. I’ll check those out

#9

I will try that. Thanks

(Alec) #10

Karen
A wonderful set of questions, which I have been thinking about as well. I am a runner, and have been fasting 2 days a week for 8months, and have been keto for 4 weeks.

What I have found is I run better in a fasted or keto state. The theory here is that when/if you are fat adapted, you can just burn fat for fuel ad infinitum. Your body will choose to burn your bodyfat if you are fat adapted if no dietary fat is available. I have found this theory works in practice for me.

A common concern I have heard is whether you can go as hard or fast on fat as you can on carbs. I am not a fast runner, but I have found no difference between carbs or fat for fuel, except on my long runs, now on fat, I simply don’t run out of energy like I used to when burning carbs. My new distance limits are now set by leg tiredness, and brain tiredness, not energy levels.

So, to answer your question directly, from my experience, I would say do not fuel up on anything before your workout. Just go out and ride!
Cheers
Alec

#11

Thanks Alec! I will try working out in a fasted state and see how I feel. I think I’m going to need to experiment. The only thing that may be tricky is when I work out in the evenings.

(Alec) #12

Karen
You definitely have to try it out. I have often worked out in the evening during a 36 hr fast, ate nothing either before or after the workout, got up the day after, and enjoyed a lovely breakfast (literally!). No impact on performance at all, if anything I felt lighter, blood focussed on my legs, not on processing food in my stomach. Give it a go!
Cheers
Alec

#13

Yes, if you’re fat adapted.

I’ve done 5+ hour bike rides and 10+ hour hikes.

I have found that I’m occasionally sluggish during the first hour, but that I feel great after that. This is particularly true if I start out too fast when mountain biking. On longish rides, towards the end of the ride, I’ve found myself waiting for fellow riders who were keeping up just fine earlier in the ride. I would speculate that they’ve burned through most of their glycogen stores whereas I still have a lot of fat left to burn. They’ve also been consuming sugary drinks or gels along the way whereas I stuck to a water + electrolyte drink. (I’ve been adding LyteShow to the water in my hydration pack.)

#14

Thanks Kevin, this is very interesting. I think i will purchase some LyteShow and see how it works. Up to this point, I’ve been drinking Various electrolyte waters such as Smart Water. I do find them helpful but don’t think they are enough.

#15

Over in the cycling forum you will find a lot of discussion on fasted workouts, use of more salt during events, and references to Phinney and Voleck’s excellent books on the subject.

#16

I just read about Smart Water. They start with tap water, distill it, and then add back in electrolytes for taste. But it can’t be much since it lists 0mg of Sodium per 0.5 L bottle.

In contrast, LyteShow has 125 mg of Sodium per each 3 ml of its electrolyte concentration. In the same 3 ml, there are also 40 mg of Magnesium, 2 mg of Zinc, 390 mg Chloride, 130 mg of Potassium, and 20 mg of Sulfate.

When I use LyteShow, I squirt roughly 9 ml into a 3 L CamelBak reservoir of filtered tap water. You can definitely taste that it’s there, but I don’t find it to be exceptionally salty or objectionable. On days when I bring two reservoirs (for 6 L total) with me, I usually use a little less in the second reservoir, but I also bring electrolyte replacement capsules with me - I’ve been using SaltStick Caps.

#17

Wait…there’s a cycling forum! Thanks!

#18

Ordering some now

(Candy Lind) #19

@KarenEckel , @richard & @ianrobo can tell you a lot about their fasted cycling. I do recall several threads talking about building up to the longer rides, and how to prevent bonking as you’re starting to build up. Have fun reading!

(ianrobo) #20

thanks Candy.

Ok first thing to say to @KarenEckelis it sounds like you are still going through Keto adaption phase and that will be tough and get the feelings you got.

As for fasting exercise, ok lets give you my story.

After being Keto adapted my plan was to go fully fat adapted and after reading up the best way was through fasted rides.

So I started off doing one hour, 90 mins etc rides to ‘super charge the system’ always making sure my cuircuit was close to home in case of issues.

after a few months I got up to 3/4 hours fasted riding and my latest example was in flanders 1st April where I did a 200km 7.5 hour ride all fasted and in VERY VERY good shape. OK I was really hungry when I finished but body wise was superb …

This was my meal

02
Screen Shot 2018-04-20 at 10.20.02.jpg1072×1302 353 KB

and just to show next day I did a 60KM ride in the afternoon, again no issues …