How much does the heat affect your running?

Here in the southern USA, it's been pretty hot and humid lately. At the same time, my running speed and comfort has been suffering. I've been getting back to running more and training to run faster this year, after finally losing 20 lbs (still working to lose more!). I really don't remember from past summers how much the heat affected me. Can anyone else share their hot-weather running experience?

Replies

  • spiriteagle99
    spiriteagle99 Posts: 3,743 Member
    It is completely normal to find that your speed and endurance suffer when it's hot and/or humid. There are formula for it, but basically, expect to be 30-90 seconds slower in summer. You should pace your runs by effort, not by the clock.

    I don't tolerate heat and humidity at all well, especially as I get older. I get vertigo and feel nauseous, my HR skyrockets, and I can't breathe. I end up needing to take breaks in order to get home without passing out. Mostly, when the feels like temp is over 90, I don't run outside. I have a treadmill, which I use a lot in the summer. This year, since I don't like to use the TM every day and we've had a lot of hot and humid days this year, I've been doing a lot of cross-training.
  • RunsWithBees
    RunsWithBees Posts: 1,508 Member
    The heat affects my running a lot! It bogs me down and zaps my energy. Sometimes I cannot finish my run and end up doing the walk of shame for the second half of my route :# and I am sure to load up on water and electrolytes but if it’s in the high 90’s or more I still have trouble sometimes, I simply overheat. Needless to say I run much better (speed and distance) in cooler temps and in the winter. I try to go for my runs earlier in the morning before the temperature gets too high but it’s not always possible.
  • Kodekai1988
    Kodekai1988 Posts: 49 Member
    Yeah the heat sucks. Particularly humid, heavy heat.

    I’m a morning runner anyway so never feel the worst of it, but if it’s going to be hot I go as early as possible and take water, even for a 5k. More of a psychological crutch but if helps.
  • Hanibanani2020
    Hanibanani2020 Posts: 523 Member
    I find cold affects it more. I can’t breathe in the cold weather
  • janejellyroll
    janejellyroll Posts: 25,763 Member
    I slow down every summer due to the heat/humidity (more the humidity). I don't even worry about it, I just accept it now because I know as we get into fall I'll get back into my groove.

    I'd rather run safely through the summer so I just work at a pace that feels comfortable when the heat is at its worst. I've had heat illness before and it's nobody idea of a good time.

    For strategies: I pick my times carefully (for me, early AM), I make sure I've got gear that keeps me safer, and I make sure I've got sufficient water.
  • BrianSharpe
    BrianSharpe Posts: 9,248 Member
    I would rather be out running at -30C than plus 30C. It gets hot and humid here and I find that, typically, both heart-rate and perceived effort are up. I try to get out early in the AM (5 or 6) before it gets too hot and run at a slower pace.
  • MarttaHP
    MarttaHP Posts: 68 Member
    My VO2max as estimated by my Garmin watch dropped by one point/unit/whatever for the duration of a recent heatwave. I also felt really lousy during my runs, especially toward the beginning. As soon as the temperatures dropped back below 22 degrees or so again (I live up north, we don't get much heat here), my VO2max increased once more.

    Your heart needs to work harder to keep you cool, so it might show up as decreased performance.
  • moonangel12
    moonangel12 Posts: 971 Member
    It is completely normal to find that your speed and endurance suffer when it's hot and/or humid. There are formula for it, but basically, expect to be 30-90 seconds slower in summer. You should pace your runs by effort, not by the clock.

    I don't tolerate heat and humidity at all well, especially as I get older. I get vertigo and feel nauseous, my HR skyrockets, and I can't breathe. I end up needing to take breaks in order to get home without passing out. Mostly, when the feels like temp is over 90, I don't run outside. I have a treadmill, which I use a lot in the summer. This year, since I don't like to use the TM every day and we've had a lot of hot and humid days this year, I've been doing a lot of cross-training.
    This is me!! Every year my heat tolerance gets worse, and this year has been BRUTAL! I had one spell of standing outside watering the garden, next to zero effort involved, and my heart rate shot up to 150! (RHR in the upper 40’s) Thankfully it came down pretty quick after I retreated to the indoors, but I was wiped out for the rest of the day and had dizzy spells for days afterwards. I have other health things going on (autoimmune) which further worsens my reaction, but one run in too hot of weather sets off a fibro flare for a week or two. It’s awful! My pace has definitely slowed, and I am having to transition to morning runs which hasn’t been easy (waking up earlier in general, to eat or not eat, often times forgetting to even consider it until I am on the road and thirsty/hungry, body still stiff and sore making my feel heavy and clunky, only having a narrow window and either kicking myself for missing it or pushing myself sometimes too hard because I don’t want to waste it, it’s just weird for me to have to actually plan in advance for a run but I am slowly getting it figured out). Colder weather has it’s downsides, but I don’t feel like it will kill me at any given moment! (Well, the day I took off thinking the roads had thawed enough and hitting a patch of ice might be the exception :lol: )

  • pondee629
    pondee629 Posts: 2,469 Member
    Heat not as much as the humidity. I do slow down when it's hot and humid. More so when it's humid.
  • DancingMoosie
    DancingMoosie Posts: 8,619 Member
    I usually trade running for swimming in the summer. This year, the pool remains closed. I decided to try to keep running and see if my body would acclimate to the heat. I try to get out and done before noon. By 10:30-11 am it's already 90+. I actually got out before 10am today! Some days are better than others. I did have one day that I just felt like I was dragging. It helps to rinse off in a water faucet, if available. I try to get 3 miles, rinse off, and then see how I feel. Walk if necessary. I always take extra water and propel packets. My pace is not as quick as during the fall/winter. I'm not pushing for speed.
  • tirowow12385
    tirowow12385 Posts: 697 Member
    edited July 2020
    Your body heats up while running or active, running while the sun is blazing hot is just asking for torture. I've done it but not many times, once when i ran a half marathon at 3pm, to avoid running and finishing in the dark. The heat didnt bother me too much, its the sudden tiredness after i ran more than an hour and 45 minutes and still had a few miles to go, did NOT expect that.
  • amykay9377
    amykay9377 Posts: 98 Member
    Yeah the heat sucks. Particularly humid, heavy heat.

    I’m a morning runner anyway so never feel the worst of it, but if it’s going to be hot I go as early as possible and take water, even for a 5k. More of a psychological crutch but if helps.

    Heavy, humid heat makes me feel like I'm breathing through a wet washcloth, and it is terrible! I live in North FL, so this is our lifestyle from May to October, so you think I'd been used to it, but noooooo... The earlier you get up, the better, though. 80º with 95% humidity is still a lot better than 95º with 90% humidity! Loose, light clothing, a visor or hat, a cooling towel, and a water bottle frozen the night before, are all in my arsenal to combat horrible temps. Also, a frozen PowerAde or Gatorade that I let thaw in my car, if I'm running somewhere away from my fridge.

    One thing I keep in mind is that Winter Speed comes from Summer Miles. If I put in the training in the summer, even if I improve by one or two seconds, it will pay off in the winter, when I can go much faster.
    I find cold affects it more. I can’t breathe in the cold weather
    I definitely prefer running in the cold, BUT the cold hurts my lungs and my asthma kicks up a lot more (I cough a lot after cold runs, too). But being in FL, we don't get that much cold weather, so I enjoy it when I can!

  • GiddyupTim
    GiddyupTim Posts: 2,819 Member
    I think it is the humidity.
    I live in Sacramento, CA. It is rather dry here. Current humidity: 37% at 86 degrees F.
    So humidity is not a problem. But heat is. We have multiple 100 degree F plus days here in the summer. And days over 90 degrees F are more common that not.
    I usually run in the mornings before it gets too hot. I only run in the serious heat rarely. But I frequently play tennis when it is very hot. Is the heat fun? NO! But it does not sap your energy and strength the way humidity does.
    Last August my son and I spent about a week in New Orleans, during a heat wave, I might add. This is how bad the heat wave -- and the humidity -- was: One evening, the temperature rose about 5 degrees F AFTER THE SUN WENT DOWN!
    I tried to run every morning, like I do normally. I'd go early, right about when the sun came up, when the temperature was below 90 degrees F. At least, I think it was below 90 degrees F. Might have been just above once or twice.
    I believe my 6-7 mile runs took me about two hours. Run. Walk. Run. Walk.
    It was fun, because it was New Orleans. The Garden District to Audubon Park and Tulane University and back. But, boy, was it hard!
  • katarina005
    katarina005 Posts: 259 Member
    Not for me because I got a treadmill for that reason. I live in Florida and it is hotter than hells hangover! I have no patience for running around humans, cracks in sidewalk or any of that!
  • katarina005
    katarina005 Posts: 259 Member
    JimDew wrote: »
    I would rather be out running at -30C than plus 30C. It gets hot and humid here and I find that, typically, both heart-rate and perceived effort are up. I try to get out early in the AM (5 or 6) before it gets too hot and run at a slower pace.

    This⬆️⬆️⬆️

    I’d rather battle the cold than be bludgeoned by the heat above about 84 if it’s cloudy, or 81-82 if it’s sunny.

    Youre sweating and more fatigued but I dont think you burn more calories. It's strain, not a better workout
  • moonangel12
    moonangel12 Posts: 971 Member
    JimDew wrote: »
    I would rather be out running at -30C than plus 30C. It gets hot and humid here and I find that, typically, both heart-rate and perceived effort are up. I try to get out early in the AM (5 or 6) before it gets too hot and run at a slower pace.

    This⬆️⬆️⬆️

    I’d rather battle the cold than be bludgeoned by the heat above about 84 if it’s cloudy, or 81-82 if it’s sunny.

    Youre sweating and more fatigued but I dont think you burn more calories. It's strain, not a better workout
    The way I am reading it, they are just saying that it’s harder to do things in the heat, not trying to claim it’s a better workout.