Afternoon 1 minute intervals

Yesterday was my planned day off. This morning did not have the motivation to go out, so I posponed my interval session to the afternoon. At 4:00 p.m. with the heat pretty high and the humidity doing its job, I headed out to the conservatory to do 10 x 1 minutes at 3k effort or so there, doing the repeats there, is not an easy feat, given the hills and turns, I warmed up around 18 mins, then started the repeats. The plan was to do first 5 repeats controlled and hammer in the second half of the workout, I started with the plan but in the first repeat the legs were fried already, I could not even lift the knees, so I gutted it out till the 8th repeat, after 8 x 1 mins , I just started the cool down that was around 22-23 more mins, did around 9.5k total. The weather was pretty hot, but I thought that I had control on it, dont know what was wrong, I just did not have it today, at least I stimulate the system somewhat and I had a good workout, was huffing and puffing hard in the last repeat, in the cool down felt better, but the legs when I tried to raise the knees to run fast, thew were fried. Have a great afternoon!