Good morning! Based on another recent post about fuel and working out, I finally decided to ask about this. Based on 23andme test results, it turns out I am genetically programmed to have much more fast-twitch muscle that slow-twitch, so much so that according to the results, ‘this is the body composition of elite sprinters’. Paradoxically, at age 48 I have never challenged myself athletically, but I’m gearing up to do so. I thought it’d be great to build strength by doing HITT and cardio workouts, and sprinting instead of long runs. But at this time I am a slender wimp with no good muscle tone/strength. So I have two questions… since I have been keto for quite some time, with my body composition, is there anything I should be mindful in terms of nutrition and powering up those fast-twitch muscles better? Also, I eat keto because on a SAD I have terrible glucose instability mostly resulting in hypos that ended up causing brain energy crisis in the past, similar to simple partial seizures (now gone on keto). But even on keto, I have to still eat every like 4 hours to keep energy stable (on a SAD it was every 2 hours!). Is this in any way related to my having so much fast twitch muscle fiber as opposed to slow twitch (think fuel type needed)? TIA!
Those fast twitch fibers are glycotolic and need glucose for functioning.
Ideally the sprint type exercises for activating these fibers should be no longer than 20-30s.
The fibers need around 3-4 minutes to recover. Creatine supplementation may reduce recovery time between efforts.
These fibers will be activated when working at max loads… 1RM, 2RM, 3RM type work loads.
The effect of activating these muscles is very taxing on the CNS.
You should also look at working the intermediate and slow twitch fibres too.
Electrical stimulation is shown to improve muscle activation times from around 0.65s to around 0.4s…. So may be advantageous to supplement your training.