In medical terms, stress is a physiological response to a stressor, which is any kind of challenge or threat to the body. This response is fundamentally the same regardless of the specific stressor, whether it's a hard run, a hard day at work, or a viral infection, although the details of the stress response vary considerably in each case. The cumulative physiological effect of all of the stressors affecting your body at any given time is known as the total stress load, or allostatic load.
As runners, it's important for us to understand these basic facts about stress, because your body can only handle so much stress at one time. Since running itself is a stressor, a major implication of these realities is that the more non-running stress you have in your life, the less running you can handle.
I was reminded of this fact within the past 10 days, when I was pulled onto jury duty. The timing was terrible, as I was also just days away from a book manuscript deadline. I felt the effects of these burdens on my running almost immediately. A few weeks ago I ran a half marathon in 1:14:55. Two days ago I struggled to run three miles at 8:30/mile pace.
Happily, though, I understood my situation well enough not to even try to run more than three miles at 8:30 pace two days ago. I cut my overall training way back as soon as I recognized that I had entered a tailspin. It's been a little scary, with my goal marathon just over a month away, but I think I'll be OK thanks to the crisis management tactics I employed.
My trial ends today, and my book manuscript is due today. Yesterday I had my best workout in a while. Things are looking up!