Course: Hampton Inn Treadmill - Council Bluffs, IA
Temp: 19 Degrees, Wind 15SE
Total Ascent: Treadmill
Avg HR: 166 bpm
Miles this week: 37
Fair speed workout on the treadmill. 15 mph winds & snow on the ground in Iowa kept me inside - hopefully tomorrow will be outside, because the treadmill sucks!
Ran the 6 middle miles at 7:13, 6:41, 6:59, 6:52. 7:09, & 7:08 for an average of 7:00. Mixed in 6:00/mile for 800M on three of the miles, with 2min rest after each. Heart rate reached 183 during.
The point of the speed workout is to increase my VO2 max, which is the maximum rate at which oxygen can be consumed and used by the body during a workout. From http://www.sport-fitness-advisor.com/ "As exercise intensity increases so does oxygen consumption. However, a point is reached where exercise intensity can continue to increase without the associated rise in oxygen consumption. This is the point of VO2 max." VO2 max can also be thought of as aerobic capacity, maximal oxygen uptake, and cardiorespiratory fitness.
Women usually have about a 30% lower VO2 max on average due to lower hemoglobin in the red blood cells (the oxygen carrier in the blood), and higher body fat ratios. Genetics also greatly affect VO2 max.
There is whole science behind VO2 max that I'm a little sketchy on. But basically, as you exercise at your maximum level for extended periods of time, you increase the body's ability to use oxygen more efficiently, thus increasing higher endurance and fitness level.
I know it's a proven scientific method that all professional athletes incorporate into their training regimens - but to this point, it seems like I have seen greater results by increasing speed and distance of my long tempo runs. This is basically a lower intensity way of developing cardiovascular capacity and thus, endurance.
The thing that I'm not sold on with speed work for marathon training is the constant starting and stopping. Typically during speed work, you run really fast for 400, 800 or 1600 meters, and then rest briefly, repeating several times. I think this type of training is mostly effective for shorter races like 5 and 10K's, because in a shorter race you can exert more energy for a shorter period of time with a short-term goal in mind.
However, a marathon is almost as much of a mental grind as it is physical. I don't see as much of an advantage in training your body for short, fast bursts when a marathon is a slower steady pace. The speed training definitely changes up the daily workouts and increases overall fitness - but mentally I struggle with them. The longer tempo runs at a faster pace than my marathon pace seem have a more direct correlation. But until professional marathoners stop using speed workouts, I'll keep doing them.