michael raiti wrote:

>I am curious of how well ketosis will work for
>individuals engaging in regular exercise programs -
>both aerobic and weightlifting. I am currently lifting
>weights 4x per week for about 75 minutes and often try
>to get in 2 30-minute aerobic sessions.  I find that
>carbs keep creeping back in. Does anyone on this list
>maintain a regular exercise programs and avoid carbs?
>My health tends to worsen whenever I to let fruit back
>into my diet, which is what tends to happen.
>
>


High-intensity weight training makes heavy use of fast-twitch muscle
fibers, which are glucose-dependant.  They do not burn fat and cannot be
retrained or reconditioned to do so.  During a workout you will tend to
draw the needed glucose from glycogen stored in the muscles themselves
for that purpose.  The liver will also try to supply needed glucose from
its glycogen stores.  If you're doing this four times a week while
adhering to a very low carb diet, you may be using glucose faster than
you can replenish it, since that will occur by the slower process of
gluconeogenesis.  In that event, you'll suffer diminished workout
capacity and probably extreme carb cravings.

Are these strength workouts whole-body or split-body workouts?  I can't
think of a good reason to do four high-intensity whole-body workouts a
week.  But it may be that you just need more carbs to keep up the pace.
I think I'd use a paleo starch such as a yam, rather than fruit, to
replenish the glycogen stores.

Todd Moody
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