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hitting the wall

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
what's happening in my body when I "hit the wall"?

For example - on today's ride (road, 15 miles, 55 minutes) I felt really strong for the first 11 miles (probably the first 40 minutes or so), but then it totally changed. It was like a a switch was flipped in my body. It was a struggle to maintain any kind of effort, and I felt totally out of gas.

What causes that? I assume my muscles run out of "energy" to burn. At that point, what do my muscles need to keep going? Or is it more a matter of conditioning, as the majority of my rides are about a hour in length?

If it's a nutrition thing, should I be eating something during the ride? or is it more about how I eat/drink during the day before the ride?

Any tips/info would be great. I've got a 60 miler in mind for next weekend, but I don't want to be 30 miles from home and have to call for a ride.
 

punkassean

Turbo Monkey
Feb 3, 2002
4,561
0
SC, CA
This isn't too scientific but are you pacing yourself? If I'm going on a long road ride I always cruise nice and easy for about the first hour to get warmed up gradually. Then I just progressively go a little faster until I feel I've hit a cadence/heart rate that I can maintain for a few hours. Then I cruise again for the last half-hour or so as a cool down.

You should eat something during a long ride and also replace electrolytes. I really like NUUN tabs to stay hydrated and Payday candy bars for quick calories and protein. Recent studies show that consuming protein during a ride can improve endurance by as much as 40%.
 

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
It's only an hour long ride - is that long enough to really need calories/electrolytes during the ride?

As far as pacing, I just ride at "a good" pace... something fast enough where I'm working a bit, but by no means do I hammer. I'm not really sure how else to explain it... if going 100% is going as hard as you can, and going 50% is going just hard enough to break a sweat and breathe hard, I probably go at 80% most of the time.
 

punkassean

Turbo Monkey
Feb 3, 2002
4,561
0
SC, CA
It's only an hour long ride - is that long enough to really need calories/electrolytes during the ride?

As far as pacing, I just ride at "a good" pace... something fast enough where I'm working a bit, but by no means do I hammer. I'm not really sure how else to explain it... if going 100% is going as hard as you can, and going 50% is going just hard enough to break a sweat and breathe hard, I probably go at 80% most of the time.
So you are hitting the wall about an hour into it? That does seem premature. Do you have a good fitness base? How much riding are you doing in general and have you been doing any kind of a routine?
 

reflux

Turbo Monkey
Mar 18, 2002
4,617
2
G14 Classified
Are you eating prior to the ride? If so, don't. I've read from a few sources that fuel taken prior to a ride can cause sugar levels to do odd stuff to your energy levels (spike and crash). From the same source, it said that we should not eat anywhere from 2 to 3 hours before the ride.
 

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
So you are hitting the wall about an hour into it? That does seem premature. Do you have a good fitness base? How much riding are you doing in general and have you been doing any kind of a routine?
yea - 45 minutes to an hour, unless it's a really easy ride, then I can go forever.

I'd like to think I have a pretty good base. I ride 3-4 times a week on average, and most of my rides are an hour long (the vast majority of my riding is done on my lunch breaks). I do a bit of trail running every now and again. I rarely exercise (ride or run) more than 2 days in a row, so I don't think I'm running down my body.

As for routine - what do you mean? Like, eating certain things a certain amount of time before I ride?
 

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
Are you eating prior to the ride? If so, don't. I've read from a few sources that fuel taken prior to a ride can cause sugar levels to do odd stuff to your energy levels (spike and crash). From the same source, it said that we should not eat anywhere from 2 to 3 hours before the ride.
Not as a general rule. I just kind of eat when I need to eat - every 2-3 hours generally. For example, today I had left over hot italian sausge at 10:00 or so (it's what I brought for lunch... I didn't bring it as fuel for the ride... it was just lunch), then nothing else before I rode, which was at 12:15.

How big a roll could hydration play in all this? While I'm not dehydrated, I'm probably not as hydrated as I should be.
 

Wumpus

makes avatars better
Dec 25, 2003
8,161
153
Six Shooter Junction
1% Few symptoms or signs of any thirst present; however, there is a marked reduction in VO2 max.

2% Beginning to feel thirsty; loss of endurance capacity and appetite.

3% Dry mouth; performance impaired.

4% Increased effort for exercise, impatience, apathy, vague discomfort, loss of appetite.

5% Difficulty concentrating, increased pulse and breathing, slowing of pace.

6-7% Further impairment of temperature regulation, higher pulse and breathing, flushed skin, sleepiness, tingling, stumbling, headache.

8-9% Dizziness, labored breathing, mental confusion, further weakness.

10% Muscle spasms, loss of balance, swelling of tongue.

11% Heat Exhaustion, delirium, stroke, difficulty swallowing; death can occur.

Percent is of total body weight. Most people sweat about 2L an hour(4lbs of water). I have calculated my loss at around 3L an hour(6lbs). If you weigh 175lbs and loss 2L an hour that is in the 2% range. If you are already dehydrated then it could be an issue.

This summer I started using half strength gatorade and really paying attention to my drinking. I usually end up losing about 4 lbs on a 60 mile ride as compared to 8lbs+ last year and I am able to maintain my pace pretty well. the days I have screwed up and not drank enough I have really suffered(weak, crampy etc.).

An hour shouldn't be enough time for you to "hit the wall" -- as in bonk -- which is a depletion of fuel. Your glycogen stores(main fuel)should last at least an hour.
 

Wumpus

makes avatars better
Dec 25, 2003
8,161
153
Six Shooter Junction
Glycogen use during exercise depends not only on the intensity but also on the duration of the exercise—how long it continues. Within the first 20 minutes or so of moderate exercise, a person uses up about one-fifth of the available glycogen. As the muscles devour their own glycogen, they become ravenous for more glucose and increase their uptake of blood glucose 20-fold or more. If you tested the person's blood glucose during exercise, you would see it rise for a while, signaling that the liver is pouring out its stored carbohydrate for use by muscles. The muscles' increased uptake of blood glucose would keep the blood glucose concentration from rising too high, and indeed you would soon see it begin to decline.

A person who continues exercising moderately (mostly aerobically) for longer than 20 minutes begins to use less and less glycogen and more and more fat for fuel. Still, glycogen use continues, and if the exercise goes on for long enough and at high enough intensity, muscle and liver glycogen stores will run out almost completely. Physical activity can continue for a short time thereafter only because the liver scrambles to produce from available lactic acid and certain amino acids the minimum amount of glucose needed to briefly forestall hypoglycemia. When hypoglycemia hits, it brings nervous system function almost to a halt, making exercise difficult, if not impossible. This is "hitting the wall" in a marathon, another type of fatigue.

To avoid hypoglycemia, endurance athletes must try to maintain their blood glucose concentrations for as long as they can. Three strategies to do this include eating a high-carbohydrate diet beforehand (see the Food Feature for a discussion), taking glucose during the exercise, and training the muscles to store as much glycogen as possible. As for taking glucose, people used to fear that sugar taken during physical activity might bring on reactive hypoglycemia due to the insulin
response to sugar. Normally insulin stimulates all tissues of the body to take up glucose from the blood and to stow it away—the wrong response for performance. Exercise is a special case, though. During exercise, the body wisely releases the hormone epinephrine, which keeps the insulin level from rising too high in response to glucose in the blood. Exercise also increases muscle sensitivity to insulin so that muscle tissue is singled out as the main recipient of blood glucose.

At the end of a competition, when glycogen is running low, glucose taken in during the event can make its way slowly from the digestive tract to the muscles. The glucose from dilute sugared drinks can augment the body's supply of glucose just enough to forestall exhaustion.

Before concluding that sugar might be good for your own performance, consider first whether you engage in endurance activity, that is, do you run, swim, bike, or ski nonstop at a rapid pace for more than 1 1/2 hours at a time? If not, the sugar picture changes. For an everyday jog or swim, sugar won't help performance, and, unless the timing is right, it may actually be a hindrance. If an exerciser makes the mistake of taking sugar within the three hours before exercise, the sugar will stimulate insulin to pour forth, causing blood glucose to drain away, and hypoglycemia during exercise then becomes likely. Research on runners shows that a sugar drink taken directly before exercise can reduce athletic performance by 25 percent.

The third factor that enables athletes to maintain adequate blood-glucose levels during exercise is training of muscles. A person trained to do the exercise at hand can work at high intensities longer than a less-trained person; trained muscles can burn more fat and thus require less glucose, even during strenuous exercise. When you first attempt an activity, you use much more glucose than an athlete who is trained to perform it. Oxygen delivery to the muscles by the heart and lungs plays a role in this effect, but equally important, untrained muscles have a smaller capacity to use their
oxygen and so depend heavily on the anaerobic breakdown of glucose, even when the exercise is just moderate. In conclusion, to maintain blood glucose for as long as possible in endurance competition, attend to diet and especially to carbohydrate intake, take dilute sugar-containing fluids if your activity lasts longer than 1 1/2 hours, and train your muscles by practicing the activity.
http://promenadetowers.com/exercise.htm
 

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
Wumpus - I don't hit the wall as in bonk... it's not like I can't function any more, I don't curl up in a fetal position along the side of the road. It just gets really difficult to push myself. I can maintain minimal effort (spinning my granny, for example), but I can't push a bigger gear like I normally would.

Does that sound like more of a hydration issue? Based on the article you posted, it seems like it.
 

Wumpus

makes avatars better
Dec 25, 2003
8,161
153
Six Shooter Junction
Wumpus - I don't hit the wall as in bonk... it's not like I can't function any more, I don't curl up in a fetal position along the side of the road. It just gets really difficult to push myself. I can maintain minimal effort (spinning my granny, for example), but I can't push a bigger gear like I normally would.

Does that sound like more of a hydration issue? Based on the article you posted, it seems like it.
I would say dehydration but that is awful quick. You should be drinking around two water bottles an hour.
 

punkassean

Turbo Monkey
Feb 3, 2002
4,561
0
SC, CA
Oh yeah dude, you need way more water than that. I pee probably 5-10 times a day and it's almost completely clear. Now overhydrating (Hyponatremia) is worse than dehydrating. More marathon runners have died from overhydarting than from dehydrating. As I suggested earlier I use NUUN tabs to replensih electrolytes. 1/2 tab per large water bottle works well.

www.nuun.com said:
hyponatremia - what is it?
we hear a lot about drinking more water being good for us but the increasing reports of hyponatremia showcase the fact that water is not always enough, especially when being consumed in large quantities over short periods of time. hyponatremia is the long word for low concentration of sodium in the blood and can occur from over hydrating with plain water. doing this, especially during exercise can deplete essential electrolytes from the body, causing disorientation, illness and in rare cases, death. for athletes, effects are generally seen in longer (and hotter) races since that’s when the levels of water intake are likely to be high.

so how does it occur?
there are a number of different drivers for hyponatremia and the answer is not simple, but if you imagine that when sweat (which is salty) is replaced by plain water (which is not salty) the bloodstream becomes diluted so there’s less sodium (and potassium etc). sodium, particularly, is essential for optimal cell function – it helps with the electrical signals that occur in our bodies and through osmosis it helps regulate cellular osmotic pressure (remember that school experiment with the bag-like thing and the salty water?). when hyponatremia occurs the cells throughout the body take on more water than normal and expand. rings and watches will get tight, you’ll look all puffy and, the bad bit, your brain swells. since your brain is in a rather inflexible skull...it gets a bit squished and that’s where the disorientation (and the fatalities) come from.

when does it happen?
we get letters and emails from people who have suffered from some degree of hyponatremia and often the common link is that they were preparing for a tough event in a tough/hot environment, like a ride in death valley or a long run in a canyon, but you can get hyponatremia anywhere that you’re consuming a large quantity of water without electrolytes. a good electrolyte sports drink will do a lot to help prevent hyponatremia and this has been well documented and accepted in medical journals. “maybe we need to make sure there is more sodium in the beverages we're encouraging athletes to drink," says nancy auer, md, vice president of medical affairs at swedish medical center in seattle. as for the "conventional wisdom" behind the handouts of free water at athletic events, "that wisdom may not be the best wisdom."

what can you do to avoid it?
our advice? be sensible. take on electrolytes, either in a sports drink, with nuun (which is obviously a sports drink...but without the sugars that most have) or using salt caps. just be aware of the potential issues of taking on lots of plain water. water’s good, there’s no argument there, but in extremes (and often less than extremes) you need more than water alone.
 

reflux

Turbo Monkey
Mar 18, 2002
4,617
2
G14 Classified
I'm with punk ass.

One thing to be careful of is to not take electrolytes if you don't need them. I can't find the link right now, but "they" say that it's bad for your body to intake too many or too few electrolytes. Apparently your body will show similar symptoms for each case. Anyway, for long rides and runs (1.5+ hours), I use Succeed S Caps. The manufacturer recommends taking 1/hour for normal exercise, 2/hour for extreme heat, and 1 per 2 hours for cool temp exercising.

As of right now, I'd say your main focus should be on hydrating. Add'l electros may not be necessary if your problem disappears.
 

Wumpus

makes avatars better
Dec 25, 2003
8,161
153
Six Shooter Junction
yep, I probably average 3 water bottles a day :rolleyes:

I'm just NEVER thirsty, so...
I use to fill a gallon water jug every morning and drink it through out the day to make sure I was drinking enough.

The wife put rubber bands on her water bottle and removed them as she refilled.


btw-the two water bottles an hour was for while you are riding. I like diluted gatorade because it has some flavor, and I tend to drink more.
 

jacksonpt

Turbo Monkey
Jul 22, 2002
6,791
59
Vestal, NY
btw-the two water bottles an hour was for while you are riding. I like diluted gatorade because it has some flavor, and I tend to drink more.
When I'm thinking about it (and consequently good about how much I drink), I do 1 water bottle and hour during the day. I can easily do 2 water bottles per hour on the bike.
 

Echo

crooked smile
Jul 10, 2002
11,819
15
Slacking at work
I wonder if it's just a weak point. Usually when I go for a long ride, about 40 minutes in I get about a 5 minute "weak spot" where I don't feel like I am able to push. But it passes and after that I'm usually good for a pretty long time. It helps to be riding with a group, so when you hit that point you can sit on until it passes, then start working again.
 

Changleen

Paranoid Member
Jan 9, 2004
14,335
2,448
Hypernormality
My urine is virtually always clear except after big nights on the piss. I drink about 2 litres a day of pure water, plus juice and beer. It's important to get a fair amount of just plain water everyday I think. As for getting electrolytes, if you eat a healthy diet, you really don't have to worry about that **** unless you're running marathons.
 

urbaindk

The Real Dr. Science
Jul 12, 2004
4,819
0
Sleepy Hollar
Back to Wumpus' post above regarding no sugar with in 3 hours before a ride if it's going to be a short, 1-2 hours, ride.

Weekdays I usually ride in the evening after work. I tend to eat lunch around noon and maybe ride starting at 6. (this will change as lack of daylight restricts my activities this fall. I usually get pretty hungry for a snack by mid late afternoon.

What can I snack on that won't mess up my ride? I typically have some fruit, a banana or what ever, around 3 and I usuallly grab a powerbar and head out the door to the trailhead. Is that a good idea? I often get syptoms similar to those jackson described and I am pretty sure I stay hydrated.