I’m 72 and on a recent ride got significantly dehydrated and suffered the consequences. Fortunately I’m okay.
The Mayo Clinic says, “As you age, your body’s fluid reserve becomes smaller, your ability to conserve water is reduced and your thirst sense becomes less acute. These problems are compounded by chronic illnesses such as diabetes and dementia, and by the use of certain medications.” Mayo Clinic dehydration symptoms and causes
Down and Out at 11,000 ft.
Most seasons I’ve been cross-country skiing by Thanksgiving. This year temps are in the 50s and I’m still enjoying cycling. Last Thursday my cycling partner and I climbed Old Squaw Pass in Colorado. Roads named “Old …” are almost always steeper than the new roads. Although the road is paved, I rode my mountain bike with low gears. We always have more fun on Old roads. Only residents go up the Old road. Everyone else drives up the new road. We rode at a brisk pace chatting all the way.
I’ve fitted my bike from my long-distance racing days with lower gears and the next day I decided to test them by climbing Berthoud Pass (11,307 ft.) in Colorado. I’ve climbed Berthoud many times including earlier this summer on my MTB.
I started at 10,000 ft. I live at 9,000 ft. so the altitude didn’t bother me initially. I was comfortably spinning 80 rpm in my new lowest gear. After about half an hour I stopped to rest, eat a granola bar and drink some coffee. Another 20 minutes and I stopped to rest, eat prunes and drink more coffee. I was breathing deeply and feeling the altitude, which always happened about then. Fifteen minutes later I rounded the last switchback breathing harder. From experience I knew the pass was wasn’t as close as it appeared so I stopped again. Time for the final push. After about 10 minutes I started breathing very hard — no different from earlier climbs. A guard rail was beside me and I aimed to ride another 100 yards to a safe place to stop. Suddenly I felt woozy, fell over and briefly blacked out. I tried, but was too exhausted to even get up. A car stopped and the people called an ambulance. I’d drunk all my coffee and was thirsty, so I asked them for some water, which they didn’t have.
A Trip to the Hospital
The EMTs arrived and checked me over physically and mentally. Physically nothing hurt, I was breathing hard (it was 11,00 ft.!) and my heart was beating hard but steadily. I knew the month, year, and the president. They asked whether Mickey Mouse was a cat or a dog and I correctly answered neither — he’s a mouse. Probably nothing was wrong but to be safe they loaded me in the ambulance and started down, but didn’t need the flashing lights and siren. They put me on oxygen, which helped a lot. They ran an electrocardiogram (ECG), noted my atria were enlarged — not unusual for an athlete — and my heart seemed fine. They didn’t have any water either.
The ER was packed so my bed was parked in the hallway for several hours and I finally got a couple of cups of water. The ER doctor checked me out, ran another ECG and still couldn’t find anything wrong. He consulted with the cardiologist on call who recommended I spend the night wearing a heart monitor and undergoing various tests.
They moved me to a private room where my first test was getting out of bed and walking to the bathroom — I hadn’t urinated since I had started riding at 10 a.m. The next test was trying to get dinner. I hadn’t eaten much since breakfast. I had a surprisingly good dinner of fajitas. Other than the fatigue from the ride itself I felt okay.
The doctor on the ward ordered a bunch of blood tests. One marker of a heart attack was a little elevated. A blood draw every four hours to check the blood marker made for a long night. No breakfast — not even coffee! — in case they had to do a procedure like a coronary angioplasty or stent implant. A tech came in and ran an echocardiogram. Next although I could have walked, the attendant insisted I take a wheelchair ride to the lab for a stress test. The lab tech was a 70-year-old cyclist so we had a great conversation about bikes and favorite rides while we waited for the cardiologist.
The cardiologist arrived, the tech informed her I was an athlete. The protocol was to get my heart rate up to 85% of my theoretical maximum, i.e., 128 bpm. I started walking at two mph on the treadmill. The speed remained the same throughout the test while the tech progressively increased the incline. After nine minutes I was breathing deeply — but nothing like how I was breathing on Berthoud — and still wasn’t up to 128 bpm. The test was showing nothing unusual so they stopped the test and slowed the treadmill while I cooled down. Most people only last four to five minutes. The test was based on the average max heart rate for people my age. Max heart rate is largely a function of genetics and my max heart rate has always been lower than average.
I explain more in this column Older Riders: Why Max Heart Rate Is Irrelevant.
In my blood work the marker that potentially indicated a heart attack had gone back down. The cardiologist read my echocardiogram, which showed her how each chamber of my heart was functioning — each was pumping blood normally. She could also tell all the valves were operating normally. She examined the data from my nine minutes on the treadmill and found no abnormalities.
A good friend of mine is also a board certified cardiologist and colleague of the cardiologist at the hospital who kept my friend informed of all the test results. My friend also saw no cause for alarm.
Physiology of Hydration
All along I’d suspected dehydration was the primary problem. I was thirsty when the folks stopped to help me and my thirst got worse as I rode down in the ambulance and waiting in ER. I didn’t urinate for about 8 hours. I was clearly dehydrated so I started researching dehydration.
The Mayo Clinic says, “To prevent dehydration, drink plenty of fluids and eat foods high in water such as fruits and vegetables. Letting thirst be your guide is an adequate daily guideline for most healthy people.“ I was thirsty climbing but I had only brought one bottle.
“The symptoms include:
- Extreme thirst
- Less frequent urination
- Dark-colored urine
These described exactly how I felt and what happened to me.
The risk factors include:
- “Strenuous exercise. In general, it’s best to start hydrating the day before strenuous exercise. Producing lots of clear, dilute urine is a good indication that you’re well-hydrated. During the activity, replenish fluids at regular intervals and continue drinking water or other fluids after you’re finished.
- Hot or cold weather. You need to drink additional water in hot or humid weather to help lower your body temperature and to replace what you lose through sweating. You may also need extra water in cold weather to combat moisture loss from dry air, particularly at higher altitudes.”
I’d been drinking coffee on the ride so I also checked whether it was a diuretic. The Mayo Clinic says, “Drinking caffeine-containing beverages as part of a normal lifestyle doesn’t cause fluid loss in excess of the volume ingested. While caffeinated drinks may have a mild diuretic effect — meaning that they may cause the need to urinate — they don’t appear to increase the risk of dehydration. “ Mayo Clinic caffeine and dehydration
II’m a coach and I read the scientific literature. I knew all of the above – I stupidly didn’t drink enough!
Next I saw a 60-year-old physician’s assistant who is a triathlete. He reviewed my chart. My cholesterol is normal, my blood pressure is normal, I eat a very healthy diet, my calcium score, which indicates hardening of the arteries is normal for my age. I take a statin as a precautionary measure.
After reviewing my chart and a physical exam, his first question was, “Were you dehydrated?” The day before I collapsed I’d drunk half a bottle on the ride with my buddy, a couple of glasses of water at lunch, nothing in the afternoon and just a glass of milk at dinner so I wouldn’t be up frequently at night to urinate. We discussed my symptoms and agreed dehydration was the probable main cause.
He reminded me that only about one-quarter of the calories I consume propel the bike and the other three-quarters produce heat, which the body sweats out. Even in the winter I’d been sweating while climbing and at my first stop shed my windbreaker.
We discussed staying hydrated during the day by keeping a water bottle handy and drinking from it in addition to drinking at meals. He agreed guys our age should limit how much we drink in the evening to reduce trips to the bathroom at night.
He asked, “Do you train hard every day?” I replied that as we age we need more recovery and I do no more than two hard workouts a week. Hard could either be intense or long. However, I had climbed briskly the day before and probably wasn’t fully recovered.”
He asked me to breath as deeply as I could and then pointed out my diaphragm didn’t descend as fully as his did. He explained my stomach and bowels hadn’t emptied fully and were blocking my diaphragm.
He advised me not to drink too much fluid, which can dilute the blood sodium to a dangerous level called hyponatremia. The general advice to drink just enough to satisfy thirst avoids hyponatremia. It’s a little more complicated for us older folks. We need to drink more than thirst signals us to drink, but not pound down the water. The key is to drink enough during the day so we’re fully hydrated at the start of a ride. Unless it’s a hot summer ride, during the ride drinking to satisfy thirst will keep us out of trouble.
He ordered a heart rate monitor for me to wear 7×24 for a week, which just concluded. I wore it including vigorous skiing, cycling and weight lifting. Nothing unusual.
The Athlete’s Heart
“Athlete’s heart is not a medical condition. It describes the normal changes that occur in the hearts of individuals who participate in intense athletic training. Such changes are subtle. They include small increases in size both of the pumping chamber (ventricle) and filling chamber (atrium), as well as proportionate small increases in the thickness of the heart muscle. Newer studies also point to small increases in the width of the main blood vessel from the heart. These changes are felt to be ‘adaptive’ – that is, they reflect positive changes that allow the heart an increased ability to supply blood and oxygen to exercising tissues. Since the maximum heart rate tends to vary by individual and by age, the principle mechanism for the heart to increase its output is to increase the amount ejected per beat (also known as the stroke volume). This is achieved by increasing chamber size and compliance.” Stanford Health Care. I’ve been an active athlete for almost 50 years and I have an athlete’s heart, which is good!
Extreme Exercise Hypothesis
The hypothesis suggests that, “potentially adverse cardiovascular manifestations may occur following high-volume and/or high-intensity long-term exercise training, which may attenuate the health benefits of a physically active lifestyle.” Extreme Exercise Hypothesis published in the US Library of Medicine National Institutes of Health.
In an article from the Cleveland Clinic Heart Risks Associated with Extreme Exercise cardiologist Tamanna Singh, MD, writes, “Extreme, long-term endurance exercise puts equally extreme demands on the cardiovascular system.” (emphasis added) Dr. Singh continues, “Moderate exercise is still the best prescription for good physical and mental health – and competitive athletes shouldn’t give up their training schedule just yet.”
I stopped ultra racing 20 years ago and now just ride for fun — I don’t even bother to count the miles! I do occasional intensity workouts on the trainer; other than those I’m exercising at a conversational pace.
You can read more in this column of mine on Anti-aging: can you exercise too much?
Two different cardiologists and the physician’s assistant performed a number of different tests, examined me thoroughly and found nothing wrong. I’m cleared to exercise. Today John and I rode again. In addition to my morning coffee I had a couple of glasses of water. I drank a mug of coffee and a bottle of water driving to meet him. After half an hour we stopped at our normal turnaround to eat and drink. At lunch after the ride I had more water. Lesson learned!
Here are three related columns:
- Heat tolerance and aging
- Twelve myths about hydration
- Nine tips for eating and drinking during winter rides
My eBook Cycling in the Heat: Hydration Managementcovers:
- How sweat cools you
- Assessing your sweat
- Fluid replacement
- Electrolyte replacement
- Electrolyte replacement drinks
- Electrolyte replacement supplements
- Electrolyte replacement food
The 21-page Cycling in the Heat: Hydration Management is just $4.99
My eBook Off-Season Conditioning Past 50 includes information on endurance and intensity workouts, cycling outdoors, indoor cycling, cross-training, strength training and more. I combine these into a sample 12-week program with options for people with limited time to train, beginning cyclists, health and fitness riders, club and recreational riders and endurance riders. The 26-page Off-Season Conditioning Past 50 is $4.99.
My Cycling Past 50 Bundle includes:
- Off-Season Conditioning Past 50 – how to best work on your off-season conditioning given the physiological changes of aging.
- Healthy Cycling Past 50 – what happens as we age and how to incorporate cycling and other exercise activities into our daily lives to stay healthy and active for many years.
- Healthy Nutrition Past 50 – what to eat and drink to support both a healthy lifestyle and continuing performance.
- Performance Cycling Past 50 – how to train to achieve more specific cycling goals given the physiological changes of aging.
The 94-page Cycling Past 50 Bundle is $15.96.
My eBook Anti-Aging: 12 Ways You Can Slow the Aging Process includes chapters on how to meet the ACSM’s recommendations on aerobic, high intensity aerobic, strength training, weight-bearing exercises, balance and flexibility. I include sample weeks and months for different types and amounts of exercise. I give you plans to build up to 100 km and 100 mile rides. I include a plan to increase over two years your annual riding from around 4,000 miles (6,500 km) to over 5,000 miles (8,000 km) a year. You can easily modify the plans for different annual amounts of riding. I discuss the importance of recovery and how to gauge if you are getting enough recovery. I combine the different kinds of training into programs that balance training and recovery. The 106-page Anti-Aging: 12 Ways You Can Slow the Aging Process is $14.99.
Coach John Hughes earned coaching certifications from USA Cycling and the National Strength and Conditioning Association. John’s cycling career includes course records in the Boston-Montreal-Boston 1200-km randonnée and the Furnace Creek 508, a Race Across AMerica (RAAM) qualifier. He has ridden solo RAAM twice and is a 5-time finisher of the 1200-km Paris-Brest-Paris. He has written over 40 eBooks and eArticles on cycling training and nutrition, available in RBR’s eBookstore at Coach John Hughes. Click to read John’s full bio.