Hitting the wall

[nun]

First the stats, I've been cycling since last summer, I'm 44, 5'11 and 200lbs.
I got back into cycling to loose some weight and now do it just becaue I enjoy it,
weight loss is a bonus.

I do 30 miles over rolling terrain Mon, Weds and Thurs at 15mph average and a longer
ride at the weekends. Right now I'm riding a singlespeed bike at 67 gear inches.

Yesterday I went on a 70mile ride (I usually do 50 at the weekends) with a few more
hills. At 35 miles I felt great and stopped for a sandwich and couldn't resist a cold
beer with it. I also drank a pint of water and had a powerbar.

When I got back on the bike all the strength had gone from my legs and the 35miles home
was a struggle. My heart raate was fine and breathing easy, but the thighs were painful.
What happened, was it the beer, stopping for 45 mins or had I just reached my endurance
limit.

[Dakota]

Sounds to me like your digestion system was busy working, at the expense of your legs. Perhaps that was a bit too much to eat.

Try the same ride next weekend but change the eating part.

[DannoXYZ]

I do 30 miles over rolling terrain Mon, Weds and Thurs at 15mph average and a longer
ride at the weekends. Right now I'm riding a singlespeed bike at 67 gear inches.That's an awfully tall gear for hills. Can you get something with more gears? Even a 3-speed coaster-brake hub would help out tremendously.

Yesterday I went on a 70mile ride (I usually do 50 at the weekends) with a few more
hills. At 35 miles I felt great and stopped for a sandwich and couldn't resist a cold
beer with it. I also drank a pint of water and had a powerbar.

When I got back on the bike all the strength had gone from my legs and the 35miles home
was a struggle. My heart raate was fine and breathing easy, but the thighs were painful.
What happened, was it the beer, stopping for 45 mins or had I just reached my endurance
limit.I don't know if the running term "hitting the wall" applies in biking. You probably bonked. You only have 2000-2500 calories of glycogen (glucose/carbs) stored in your body. Doing hills in big-gears will stress your muscles tremendously, probably close to their LT-lactate threshold. That's the cause of the sore legs. This means you're burning off mainly your stored glycogen very fast, within 2-2.5 hours maximum. Once that supply is gone, you bonk which feels like your legs turned to wet-noodles with no power, you feel cold & clammy, and you're desperately scanning the ground and trees for food to eat.

To prevent the bonk, use easier gears to spin your legs faster. They can generate the exact same power-output, but at a lower force on the pedals. This keeps them further away from the lactate-threshold and they burn more fat and stretches out your glycogen supply.

1. Eat and drink more from the very beginning of the ride. You'll want 1.0-2.0 bars per hour which is around the maximum of 200-300 calories/hr your body can digest.

3. Drink A LOT more water. About 18-24 oz. of water per hour. This water replaces what you sweat-off in 1:1 ratio.

2. Also use an energy-drink with electrolytes to replace the sodium that you sweat away, about 500-700 mg/hr is about right depending upon the outside temperature. If it's really hot, you'll want to fortify the drink with some electrolyte supplements.

[ericgu]

I'm not sure whether you bonked or not. I've bonked a couple of times, and it's never been a case of my legs hurting. More like I couldn't get any speed no matter what, and I really didn't want to keep riding, and got really hungry. It's in the "I never want to do that again" category.

Another item that goes against the bonk is that it happened right after you had stopped and eaten. You'd expect that your blood sugar would have gone up after you had eaten.

I agree with Danno about what to do. I'd also recommend that you start weighing yourself before and after the ride to see if you're taking in enough liquid.