I've noticed over the years that when I'm tired in my training that I tend to sweat at a lower heart rate / or pace.
The thing I'm doing now is watching my heart rate and noticing when I start to break a sweat. I am writing down the heart rate this happens. Today this happened at 135 heart rate.
To do this, I gradually increase the pace( on a treadmill) until I notice when sweat break.
When I'm tired, I could start breaking a sweat at 120 or even 110 heart rate.
Now all the variables are the same because I'm on a treadmill, same temperature.
Has anyone experienced this sweating earlier when tired in his or her training?
I wonder if it is a good measure of when to back off and when to jam.
I don't know, but the relationship is most definately there. When I feel awful, I sweat more and with less actual exertion although mentally the exertion is much greater.