Unseasonable warmth and the organizers’ failure to plan for that even knowing the forecast in advance. The biggest issue was lack of water. Water/Gatorade stops were advertised to be every mile or so but there was NO water till mile 7… and they ran out of cups at every station past mile 7.

Carnage at the NYC Marathon too. It's hot out.

Although it’s hot, it’s not that hot. With proper hydration, it should be fine.

It was definitely not having enough hydration stations! I am a regular runner and it was definitely the hardest I’ve run in a while due to the heat and the lack of enough hydration stations

There was a water stop somewhere around mile 2-3 from what I remember.

FWIW I thought the race was reasonably well organized and staffed. I took water at every stop and was glad I did so. Just speculating, but runners themselves may not have been prepared for the warm weather and may have thought they could do without slowing down for water.

Anyone who thinks running long distance is actually healthy is crazy

I run the Cambridge half every year and that was not normal! It was way to hot and humid for November and I think all the runners (myself included) were having a struggle.

Generally marathon organizing experts indicate that a marathon should be held at a temperature of 45-50 degrees. If it's 70, they should strongly consider canceling or suspending the event until cooler weather. We were at, or damn near, that. Your body heats up a ton when you're running those crazy distances.

There's a reason marathons aren't held in hot weather.

This incredibly anomalous weather is mostly to blame but the event coordinators should have compensated a bit with the demand for more hydration.

Any full marathon that is in weather close to +70F can be perilous due to hyperthermia.

I ran it for the first time on Sunday and noticed something seemed off by the number of people struggling or fading out at the race went on. Pretty disturbing and didn't know if things like that were normal.

Would they really cancel a major marathon like NYC or Boston because it's 70 degrees?

Probably not at 70, but if it was pushing 80 they definitely should or they'll get tons of people passing out

People forgot how to walk?

Did you drink ALL the water?

Likely a combination of weather and, honestly, maybe some folks who had contracted COVID in the past year and hadn't recovered as much as they thought they had... but hot weather would be enough.

I don’t know if this is actually a thing. I have done many June marathons and they are often as warm. It is the organizers’ responsibility to offer proper hydration.

I ran it too, it was bad. I thought something bad happened considering so many people were passed out. $110 race and no water on the course or at the finish? Ridiculous.

When did you finish? There was water when I finished, but strangely no Gatorade. Just an orange, a banana, and water

I was shooting for a 1:55, finished in 2:17. No water at the finish, bins that previously held oranges and bananas were full of garbage. Goody bag had a frisbee and Twix flavored popcorn in it.

I've run it several times and this one just seemed to be not organized well. I finished around 2:10, there was no fruit left at all. I think there were only 4 or 5 water stations on the whole route. By the time my wife finished, there wasn't even any water left at the end. There were so many people needing medical attention!

Also, less seriously, there was no afterparty this year. Last year had CBC slinging beers on First St. Would have been perfect weather for it this year!

Can you wear your own hydration vest for the Cambridge half?