Lessons From Exercising Until Hitting the Wall: A Reflection

PHOTO: Dan Childs, ABC News Medical Unit Managing Editor, ran on a treadmill until he hit the wall under the watchful eye of exercise physiologist Harry Pino at the NYU Langones Sports Performance Center. PlayMichael Nedelman/ABCNews
WATCH Highlights and Lowlights: Dan Childs 'Hits the Wall'

I was certain my eyes were going to pop clean out of their sockets. Logically, I knew it couldn’t happen. But in that moment, I was sure they were going to shoot right out of my skull and bounce across the floor like two ping pong balls.

What did I learn from hitting the wall? Beyond the nausea, tunnel vision, burning lungs, and jelly legs -- it just plain sucks.

But ABC News' “Hit the Wall” livestream offered some much more profound insights on pushing my workout to the max -- which is what many people who hate to exercise strive to avoid.

To help the ABC News Medical Unit further explore this phenomenon, NYU Langone’s Sports Performance Center generously allowed us to take full advantage of its facility. It also offered the services of two of their exercise physiologists, Harry Pino and Heather Milton -- our tour guides along the path to physical exhaustion.

So, what were the major lessons learned?

Lesson One: There is more than one “wall” … and the one I hit was certainly not the worst. As Pino and Milton explained, what I encountered is known as the lactic acid wall. Lactic acid is a pesky byproduct of the body’s normal functions, and your muscles ramp up production during exercise. This lactic acid is the reason for the “burn” you feel when you are pumping iron or squeezing out that final quarter mile on the exercise bike. Once your muscles start producing lactic acid faster than your body can get rid of it, the acidity builds up in your muscles until you are forced to stop exercising. That was the point on the treadmill when my legs threw in the towel.

But there’s another, taller, nastier wall out there -- one that can send you to the hospital due to muscle breakdown and kidney injury. This wall involves the total depletion of the body’s carbohydrate stores needed for cardiovascular-exercise.htm" id="ramplink_physical activity_" target="_blank">physical activity. The difference between these two walls is a bit like the difference between your car overheating for a bit as opposed to completely running out of gas. In one of these instances, you can shut off the engine for a while and you’re good to drive again. In the other, you’re stuck, going nowhere. This second wall, aside from taking a much longer amount of time to reach, is far more dangerous.

Lesson Two: There’s much more to fitness than just being fit. Here’s the thing: I’m not an athlete. It’s something that has been pretty clear to me from a young age, reinforced during countless humiliations during pickup football games and a lackluster childhood career in YMCA baseball. So, when I received my extensive analysis from NYU Langone, I was both surprised and humbled.

The surprise? My VO2 max, a measure of my body’s capacity to use oxygen to fuel exercise, was 50.7 mL/kg/min -- a level that Pino described as “not bad for an old guy.” I’ll take it. And apparently, my anaerobic capacity -- in other words, my body’s ability to generate bursts of power for a short period of time -- isn’t too shabby.

But beyond that, things dropped off pretty precipitously. Endurance is a problem. My running mechanics are strange and problematic, characterized by imbalances and inefficiencies that I never noticed before. For example, I tend to put my leading foot too far forward, my knees aren’t flexed nearly enough, and I bounce down the pavement as if on a pogo stick. All of this puts more stress on my feet, legs, hips and spine. The sobering conclusion: “This increased impact may lead to injuries such as: tibial stress fractures, patellofemoral pain, and hip pain.” Yikes.

Additionally, Milton’s evaluation of my movement revealed that I am at risk of exercise-related injury. One particularly notable issue: “Decreased gluteus medius strength and delayed gluteus maximus activation.” Translated: I literally need to get my ass in gear.

Fortunately, she reminded me, these are all things that the sports medicine center could help me address. Along with the full report, she sent me away with a list of exercises designed to strengthen these weak spots, as well as drills designed to address my problems with aerobic endurance. Apparently, mixing a bit more cardiovascular exercise into my workouts will do me a world of good.

Lesson Three: There’s really no need to ever hit the wall. According to the U.S. Centers for Disease Control and Prevention, we should all be getting at least two and a half hours of aerobic physical activity a week. In reality, only about one in five of us get this minimum recommended level. We can blame it on time constraints or access to a gym, but part of the problem may very well be that many of us secretly fear the unpleasant feelings that come along with hitting the wall. Fortunately, there is no need to push it to the limit when it comes to getting in better shape. A brisk walk, walking up and down the stairs -- these and other moderate-intensity exercises can do wonders for your health. And in the end, focusing on these simple steps is far healthier than aiming for the wall.

Something I’ll keep in mind the next time I lace up my shoes for a run.