Question: Last winter I adopted a low-carbohydrate diet and lost 20 pounds. I’m continuing the diet but wonder if lack of carbs is the cause of my struggles on the bike. While I’ve improved my average speed on solo rides, I can’t keep up with my friends on Sunday morning. I’m fine when the pace is steady, but if they sprint I’m off the back. How do I maintain low body weight and still get the necessary fuel? — Tom D.
Coach Fred Matheny Replies: The research is pretty clear on a low-carb diet. It might help you lose weight quickly, but it doesn’t provide enough carbohydrate to keep your muscle glycogen level sufficiently high for performance riding. It doesn’t help to lose 20 pounds if you end up slower rather than faster!
The reason your average speed has improved but you can’t stay with the group is simple.
When you don’t have carbs to burn, your body primarily runs on fat. It can simmer along steadily, but it can’t go fast because high intensity requires lots of glycogen.
When your buddies pick up the pace, you don’t have “afterburners” that allow you to jump quickly and stay with them.
I suggest increasing the percentage of carbs in your diet. Add whole grains, fruits and veggies. Reduce fat and protein slightly so you aren’t taking in more total calories and gain weight.
I bet you’ll feel better and perform better, too.
Hi, I’m a cyclist and have been on a slow carb diet. I’ve noticed the following.
During the first 3 rides since slow carbing, I literally ran out of energy after 30 minutes. The first time, I had protein-rich foods to snack on and they didn’t help much. After that I packed pure carbohydrates (Clif’s Blocks) and they helped significantly. Since then, I always bring carbs just in case, but I haven’t needed them on rides up to 2 hours, though the last 20 minutes or so are a little slower than they’d be with carbs. Also, taking carbs while riding didn’t seem to reduce my fat loss.
Ned B says
Too many studies based on people that just adopted a low carb diet and haven’t reached the level where they body isn’t relying on carbs anymore. There are several studies now that prove a low carb endurance athlete doesn’t have the “bonks” that a higher carb diet athlete has. So do better research based on more valid studies.