T Nation

Feeling Out of Breath on Low Carbs

Anyone else feel this way? I would love to imagine that I’m oxidizing fat so rapidly that I’m using a ton of oxygen, but I don’t have a clue. The fat is coming right off (not much to begin with) so I’m not complaining -just curious.

Any form of HIIT or similar activity can be hard if you’re in ketosis, especially if your calories are also low.

[quote]dnlcdstn wrote:
Anyone else feel this way? I would love to imagine that I’m oxidizing fat so rapidly that I’m using a ton of oxygen, but I don’t have a clue. The fat is coming right off (not much to begin with) so I’m not complaining -just curious.[/quote]

Bump for this also.
I get the same feeling when going keto. I also get a build up of lactic acid very easy. For example walking up a flight of stairs I get winded and my thighs are already burning.

Or your just out of cardio shape…

It’s because you’ve severely limited your body’s preferred fuel supply for high-intensity activity.

For this reason I think easy-to-moderate steady-state cardio makes most sense when going low carb.

I read that it takes a pretty long time to adjust. I did 1 whole week of very low carbs (0-10). When I started working out again my #'s were low & I was sucking so much wind. I felt possessed & had 2days of cheating. I feel really guilty. I think I’ll stick to carb cycling & leave the 0 carbs for the off days.

[quote]HK24719 wrote:
It’s because you’ve severely limited your body’s preferred fuel supply for high-intensity activity.

For this reason I think easy-to-moderate steady-state cardio makes most sense when going low carb.[/quote]

Spot on, your body just isn’t used to converting other nutrients into fuel. You’ll get used to it eventually, it isn’t fun, but if it was then we wouldn’t stand out from the pack now would we.

[quote]Fuzzyapple wrote:
Or your just out of cardio shape…[/quote]

I’m in decent shape. I was jogging at 7.0 for 45 mins no problem on treads. I feel out of breath just sitting around. It’s a weird feeling. I currently use an elliptical at a super slow pace with lots of resistance trying to keep my hr low as possible.

[quote]dnlcdstn wrote:
Fuzzyapple wrote:
Or your just out of cardio shape…

I’m in decent shape. I was jogging at 7.0 for 45 mins no problem on treads. I feel out of breath just sitting around. It’s a weird feeling. I currently use an elliptical at a super slow pace with lots of resistance trying to keep my hr low as possible. [/quote]

Yeah after I read posts after what I said, lets just say I learned something :stuck_out_tongue:

When I go low carb, say below 100 grams a day, I usually feel a bit weird the first 1-2 days then I start feeling great and full of energy.
It’s kinda sad since I really love carbs but my body really thrives on low carb so I have to make the “sacrifice”.

I don’t think you should be out of breath with low carbs. You’ll tend to feel sluggish and incapable of much movement, sort of like the runners describe “hitting the wall”, or maybe “bonking” to cyclists, but you shouldn’t have difficulty breathing.