My quads are getting fatigued during cardio

thirstyflea

I've been working out 5-6 times a week, 2-3 days with a trainer, and 2-3 cardio (like dance or step classes).

A few weeks ago, I noticed that my quads get really fatigued about 10 minutes into a cardio class. And it happens consistently now. I'm not winded at all, my legs are just tired. I pride myself on how strong my legs are (I can squat like a pro, deadlift 190, and leg press 210- not every week though!), but I do 10 minutes of step aerobics (bench with 1 riser- is that 6-8 inches?), for example, and my quads are tired. Even squats & lunges during class tire out my legs, but not really when I'm with my trainer (who I feel pushes me much harder).

I eat a protein bar about an hour before class, and I don't seem to get this fatigue while strength training, even if I have to do tons of lunges or squats, etc. I do the classes so I can get my HR up, but that's barely happening in this specific class. My trainer doesn't know why that's happening to me, as he knows how strong my legs are. I get nervous now before class- even my instructors have noticed the change... Am I just weird??

sijomial

Few ideas:
1/ Have another rest day a week. Give your legs a break.
2/ You are working hard on low calories, eat at maintenance for a couple of weeks?
3/ Do you do any low intensity cardio to build your base endurance? Have a read of this article (it's based on cycling but applies to any cardio training). It's pretty dull to do but has really made a big difference - I've really noticed improved endurance after a few sessions.
http://www.bikeradar.com/fitness/article/heart-rate-monitor-training-for-cyclists-28838/

trigger2354

I'm not an expert so take this with a healthy dose of skepticism: I wonder if you have preponderance of fast twitch muscle fibers in your legs vs. slow twitch. Fast twitch fibers contract quickly and generate considerable force, but they also fatigue much more quickly than slow twitch fibers. Power lifters have predominantly fast twitch muscle fibers because the sport demands rapid, forceful muscle contractions over very short time frames.

Endurance athletes, on the other hand, have a preponderance of slow twitch fibers which don't have the contraction speed or strength of fast twitch fibers, but have much greater endurance and aerobic capacity.

See this article for more info http://ccahill.hubpages.com/hub/Fast-Twitch-vs-Slow-Twitch-Muscle-Fibres-Endurance-or-Strength

thirstyflea

Those are great suggestions, thank you so much! And I will read both of those articles right now! I probably should take another day of rest somewhere, but it's hard to stop my "daily workout routine", at least psychologically, as I'm trying to lose weight, so I have the misguided belief that if I miss a day, then I'll gain weight. I'm sure it's not true, but just one of those mental hurdles. I have tried increasing my calories on work out days, but again, mental hurdles...

Endurance has never been a strength of mine, so that fast twitch vs. slow twitch actually sounds logical...

Thank you both!

prokomds

Yeah, I would say the most likely culprits are...

1) You need to rest up some. Maybe you need 2-3 rest days each week instead of 1-2. If it was me, I'd consider cutting out one of the days of cardio

2) You're not eating enough. I don't know your height/current weight, but I would bet that you should be eating more, even when you're not exercising. You could try adding an extra 200ish calories every day and see if that makes the difference.

Congrats on such awesome progress turning your lifestyle around! Just understand, you don't have to go from nothing (no exercise, no self control over your eating) to everything (STRICT calorie control, what you're doing now, and exercising so much)

Be very careful, also. You're suddenly putting all this extra strain on your body, and you're feeling fatigue from that. DO NOT be afraid to back off a little until you recover. Being fatigued puts you at a higher risk to injure yourself -- what would you rather, cut back for a few weeks, or risk hurting yourself and putting you back for months? I don't want to scare anybody, I just want to point out that you need to listen to your body

scottb81

Your lifting has been primarily developing the fast twitch muscle fibers. The cardio is using primarily the slow twitch muscle fibers. They will take time to develop. You may also need to take a day or two off for recovery.

The protein bar before working out isn't doing anything for you. If you think you need some energy eat some carbohydrates beforehand.

DavPul

My guess is a glycogen issue. Instead of a protein bar try 2 tbl of honey