Muscle Glycogen Question (Weights before Cardio?)

gogetemrogue

I have heard that cardio depletes muscle glycogen after around 20 minutes, and for that reason you should do any strength training before cardio so that you are a lower risk of injury, and you get the supposed benefits of cardio while glycogen depleted. Does this ring true regardless of sector being trained? For example, training arms before or after a treadmill workout?

Sorry if I have any of the info wrong, it's been a while since I looked into this stuff.

Lean59man

I do weights first.

Doing cardio first would tire me out.

Common sense.

sijomial

20 minutes? Nope, nope, nope.
More like two hours of intense cardio.
Besides which you aren't solely burning glycogen at the vast majority of cardio intensities let alone a cardio warm up.

Whether you do cardio or strength first is down to a whole load of "depends".....
Intensity, goals, capabilities, personal preference for starters.

For the majority of everyday gym goers and their everyday workouts it's an irrelevance.

BTW - my personal preference is alternate days. I also don't fuel cycle rides until they exceed two hours at a decent intensity. The only time I've become completely glycogen depleted (bonked or hit the wall as runners would call it) was after five hours and with badly planned fuelling. There's no mistaking it when it happens!

cwolfman13

You're not going to deplete glycogen stores in 20 minutes...it'll take a good couple hours of relatively intense cardiovascular activity to do that.

I typically do cardio on non-lifting days. Most people I know who are lifting with purpose will lift first to get the most out of that session and some may follow that up with some lite cardio work...most people I know who do higher intensity lifting and higher intensity cardio do these things on alternating days, not in the same session.

gogetemrogue

Good to know I was wrong about the twenty minutes! Should add that my particular goal is fat loss, not bulking.

AllanMisner

Intense cardio will take you nearly 2 - 2 1/2 hours to burn through your glycogen stores (that's why marathon runners bonk at the 16 - 19 mile mark). Weight training burns even less muscle glycogen than cardio. That said, you will fatigue based on your fitness level. Unless there is a lifestyle reason you can't, you'll have more energy for each workout if you split them up on different days.

Allan Misner
NASM Certified Personal Trainer
Host of the 40+ Fitness Podcast

NorthCascades

The glycogen thing is absolute bro-science.

Most people do whichever is more important to them first so as not to compromise it. Personally, I lift at lunch and ride a road bike in the evening, which gives me enough time to recover.

Cherimoose

roguepsyche wrote: »

Should add that my particular goal is fat loss, not bulking.

The timing of your workouts won't have a noticeable effect on your long-term fat loss results. The same with the timing of your meals by the way.

SonyaCele

roguepsyche wrote: »

I have heard that cardio depletes muscle glycogen after around 20 minutes, and for that reason you should do any strength training before cardio so that you are a lower risk of injury, and you get the supposed benefits of cardio while glycogen depleted. Does this ring true regardless of sector being trained? For example, training arms before or after a treadmill workout?

Sorry if I have any of the info wrong, it's been a while since I looked into this stuff.

glycogen levels aren't going to affect your risk for injury as much as just plain old common sense. . Now if you ran hard for an hour and then jumped into some hard core strength training like max effort squats, fatigue is gonna hit you hard and you aren't going to be able to train as strong or as long, and if you don't use common sense you could get hurt.. But if you are just doing some cardio and then doing a few sets of free weights, whether you do cardio before of after isn't gonna really matter much.