It's you... Not Me

Anyone who knows me, knows I love coffee. It isn't the caffein, it isn't a crutch per se for getting up; it's the taste. There are only two drinks I could enjoy any time of day, regardless of situation: coffee and red wine. (Don't take that the wrong way, I've never had red wine in the morning, that I remember.) So, as part of my normal habit, on the weekends, I'll brew a few espresso drinks during the day because I'm home and I have the time. My normal during the week routine is to make a double or triple espresso drink in the morning and not have any more during the day. Usually, Josh and I have already worked out before coffee even comes into question, so I rarely deal with training after having had coffee. Yesterday, however, we missed our morning session and decided to hit the gym around 1:30 in the afternoon. By that time, I had already had two or three coffee based drinks and hadn't thought much of it. I hadn't been on the treadmill for more than 15 minutes since Wednesday, so I told him that I wanted to spend a good half hour running.
Thinking that I'd be able to do around 3 1/2 mi. in under 30 min. I decided to push it a bit. I started at the normal 6 1/2 mi/hr pace and got my heart rate into my normal 170 zone. After eight minutes, I usually start pushing the pace up in 1/2 to 3/4 mi/hr increments. So, I went up to 7 1/4 mi/hr. My heart rate went up like it normally does. Usually, I hit 180-182 and then it slowly goes back down to the mid 170's (now, if I were really in shape, I'd be able to nock a good 10 bpm off those numbers). This time, it hit 180, stayed there and then went up to 185. I struggled to change my stride and/or relax to reduce the heart rate. I can only go with my heart pumping at 185 for so long. I hit the wall somewhere at the 1.2 mi mark and lowered my pace to 3 mi/hr to reduce my heart rate to reset. Usually, if I can't get my heart rate down through relaxing or changing my stride, I'll go down to walking pace and reboot. I reduced my heart rate to 140 and started over with 6 1/2 mi/hr. After going through my startup routine again, I tried to push my pace above 7 mi/hr. Wham... again, 185. I was starting to get pissed. How the heck did I go from being able to drive away at 7.7 mi/hr last time, for over 10 min., and now I can't get more than a minute at 7 mi/hr without my heart going to the top end of my zone? I ended up going through the same routine above again before finally walking when I hit 3.2 mi. and then blasted away for .2 more mi. at 7.7 mi/hr until I hit 3.5 mi. I was dead when I got done, though, and couldn't understand why.
During the second part of yesterday's workout, I was telling Josh about it and he asked if I had any caffein... What? My mind started connecting the dots. Normally, when I go running, either I haven't had any coffee or it has been a few hours since. This time, I had a cup almost right before going to the gym. He mentioned that many people's heart rates are affected by 10-15 bpm by caffein. While they won't necessarily notice it during a normal day's routine, running really brings out the difference. It certainly did for me... I thought, though, that maybe it was simply a fluke and to test the idea, I decided to push it harder than I normally would when we went in this morning. I didn't run because I just did legs yesterday and I was somewhat sore, but I got on an elliptical machine and went through a routine I'm very familiar with and pushed it a few notches harder than I normally do. My heart rate never went over 170. (I know the results from running would have been slightly different, but not much.) So, there we have it. I can't drink much coffee before hitting the treadmill. It almost ruined yesterday's workout because I wanted to give up after a mile, but luckily it didn't go that far.
So, my advice (at least to myself) is to watch the caffein before an aerobic workout. I won't be doing that again.