Feeling woozy after first sub-zero (°C) ride
Having recently moved to central Sweden, I'm getting to grips with living in a cold climate for the first time. This probably won't count as cold by most people's standards on this board, but temperatures here have dropped about 5° in the past week and are now hovering around 0-2°C (32-35°F) at midday.
This morning I set out on my regular short Sunday morning ride: 1 hour spent repeatedly going up and down the only hill anywhere near where I live, followed by a 20km loop on flat roads. It was -4°C (25°F) when I left the house and 0°C (32°F) when I got back, so I was wearing several layers, long tights etc. and felt pretty good for most of the ride, barring the inevitable cold fingers and toes.
Then, about 10 minutes before I reached home, I suddenly hit a wall: all the energy seemed to drain out of my legs, I felt faint, and when I reached for my brake levers I found my fingers were too numb to grasp them unless I focused all my concentration on it. I struggled home on autopilot, almost fell over from light-headedness when I got off my bike, and gratefully stumbled into my well heated apartment. After a few minutes I started to feel cold again, so I put on an extra pair of trousers and a jumper over my cycling clothes, but before long I was buried under my duvet, shivering and teeth chattering uncontrollably.
Three hours later, after a very long hot shower and several mugs of hot cocoa, I'm pretty much back to normal (still feeling a bit light headed), but completely at a loss to explain what happened to me (other than that I obviously overdid it and need to take it easy until I get used to the colder weather).
Have any of you experienced these kinds of symptoms after riding in winter temps? Do I just need to keep my energy levels up by eating more when it's cold so that I'm not running on empty by the time I reach the end of my ride? Any suggestions or similar experiences are much appreciated.
How was your hydration? A lot of people don't drink enough the colder it gets, and sometimes actually sweat a lot more due to wearing too much clothing and can become dehydrated a lot easier. The lightheaded feeling, fatigue, and chills/shivering can be signals of dehydration. Other than that it's a lot of trial and error to find the right combo of clothing for the effort and temperature in colder weather.
you did not state if you were urinating at all. On a ride of that length, you should of at least had a full bladder when you got home, or you were running the risk of dehydration.
I'm hesitating between light hypothermia and hypoglycemia but because it happened suddenly i would go for hypoglycemia even though there is no information regarding your heart beating like crazy.
There is no symptom of dry mouth, dry eyes, being thirsty, lack of sweat neither
I though about light hypothermia first because of several factors:
-temperature range between 20F and 40F which is the range of false sense of security
-time spent outside : 1hr
-sequence of efforts : intense first then light
What would result in light hypotermia at this temps range is the fall sense of security. Riders feel it's not cold enough so they wear just a little. Then come an intense effort which makes the riders sweat. The sweat contaminating insulation layers decrease the insulation capacity of those layers. Then the body start getting colder. Here comes the low intensity part which prevent the body from gaining back the heat lost and even result by more heat loss by the body. The body try to compensate by increasing the body temperature up to a certain point where the body finally give up. Resulting in those symptoms.
But here i think it's more hypoglycemia. You probably run short in glycogen/glucose.
Did you eat properly before and during the ride?
Hi guys, thank you for your responses. I definitely agree with erig007 about the false sense of security: I clearly underestimated the conditions. In the long run it's probably a good thing for me to have a little scare like this to teach me to be more sensible in future. It's going to be getting a lot colder here soon (unprecedented territory for me), so it's a lesson worth learning.
In answer to your questions, I only had one water bottle with me, which I drained during the ride, and I had a good breakfast before setting out but nothing to eat while on my bike. Bladder was pretty full by the time I got home.
It just surprises me how much of a difference a small dip in temperature can make. All the other variables were the same as usual - I follow the same circuit with the same water & food pattern at least twice a week and don't really push myself at all physically (I go at quite a leisurely pace), but drop the temperature by a few degrees and my body has a completely different reaction. Oh well, *shrugs*, now I know to be more careful.
just another gosling
Hypoglycemia. Nothing else. You need more to eat when it's cold.
bonking is bonking in hot or cold. eat better before you leave, snack along the way if you need to and keep hydrated. I'm thinking the temps had little to do with the problem. My ride today as at -10F...
In the right lane
If the weather is colder than what I'm used to, I generally take a more conservative approach.... try shorter trips at first, then make them longer if it feels comfortable.
I seldom stay out too long in colder weather. Also, it's considerably more work to bike in colder weather. Cold air is denser and harder to push through.
I tend to go slower, try not to breath through my mouth and go home when my toes start to get cold. Still, it can be quite fun... just that you need to take things a bit slower.
never said it before...
I had to go back and double check the temps mentioned. I'll add to what I said before in that I think you just bonked. Period. That said, and I don't mean to be rude because I try not to be, I also have to say that if you think those are cold winter temps then it's time to htfu. I realize that southerners react to cold temps differently and it does take time to acclimate so time to do that acclimating stuff. I think I'll start a thread on winter clothing.
Originally Posted by EntenteCordiale
Nothing better to do other than eat better and keep spending time on your bike in cold temps. My ride today was +20, which is 30 deg warmer than yesterdays ride. Just don't let the cold keep you from riding. Keep adjusting clothing, gear, cadence, tire pressure...don't let yourself get soaked with sweat and be prepared with clothing and gear for fixing a flat which is a challenge in the dark and cold.
Sounds like hypoglycemia caused hypothermia. Your body needs fuel to burn to keep warm in those colder temps. If you don't have the fuel, you get hypoglycemic, and then if you keep pedaling you are asking your body for more fuel which makes the hypoglycemia worse and your body just can't keep up with the demand.
In cold weather there are a couple of areas of the body where you can lose a lot of heat. The head, so keep it covered. The hands and feet---ditto. And the lungs. Wear either a buff rag, or if it's really cold I'll put on a Neoprene ski mask covered loosely with a Shemagh.
I did about six miles or so Friday morning in the same temps you were in with no problem. Dressed in a pair of sweat pants, t-shirt with a flannel shirt, fleece lined jacket, beanie and gloves. Stopped at a grocery store to hydrate, and Carls Jr. for breakfast before heading back home. Eat, hydrate, ride....repeat!
I've had this experience before and I have to agree that it is a combination of mild hypothermia, hypoglycemia, and dehydration.
Originally Posted by EntenteCordiale
It's easy to get dehydrated in the cold because you don't feel very thirsty and don't need the water to cool off. You need more calories to keep your body warm. And it's easier to get your core cooled off just a little more than you think while exercising in the wind chill.
Dress a very little bit warmer and more breathable so as to stay warmer and retain less sweat in the clothing. Drink often and take food with you and eat while riding. When you get home if you feel a bit chilled get some hot drink and have a hot shower as soon as possible and don't sit around in those cool sweaty cycling clothes. They are designed to breath and keep you dry while cycling but are not good insulators for sitting around. Eat some hot food as soon as you get warmed up but not before as your body has to use heat to digest food.