Key Elements to Getting FIT(T)
Question: “Recently, I have begun running 10K races. I enjoy running and want to improve my race times. Aside from mileage, what other factors should I consider when making my workout plan?”
To improve aerobic (cardiovascular) fitness, the American College of Sports Medicine (ACSM) recommends a workout regimen that adheres to the FITT-VP principle of training. The acronym stands for frequency, intensity, time (duration), type (of exercise), volume and progression. Consider these factors when formulating your workout plan, as each plays a role in the development and improvement of aerobic fitness.
How often you exercise will depend upon your goals and the intensity of your workouts. Three workouts per week is considered the minimum required to improve aerobic fitness. More are recommended if you expect to realize significant fitness gains. Exercising five or more days a week can provide additional benefits, particularly if the goal is to burn calories, lose body fat and improve aerobic fitness.
How hard you exercise affects the amount of oxygen consumed and energy requirements of the activity. Monitoring heart rate is a convenient means of estimating exercise intensity. The more rapid your heart rate during exercise, the more intense the effort. The minimum intensity required to stimulate improvements in aerobic endurance is about 60 percent of maximum heart rate (HRmax). This is commonly referred to as the aerobic threshold. There is also an upper level of intensity, referred to as the anaerobic threshold, that coincides with exercise intensity of approximately 90 percent HRmax. An exercise heart rate that falls between the lower and upper thresholds is within your target training zone.
Estimate maximum heart rate by subtracting your age from 220. For example, a 40-year-old would have an estimated HRmax of 220-40=180 beats per minute (bpm). The target training zone for that person would range between 60% (108 bpm) and 90% (162 bpm) of HRmax. To check heart rate during workouts, stop exercising for a moment and locate your pulse by resting the index and middle finger at the base of the wrist or at the side of the neck near the Adam’s apple. Count the beats for 15 seconds and then multiply by four. Your exercise heart rate should fall somewhere between the lower and upper boundaries of your target training zone. After a while, you will be able to judge whether you are exercising “in the zone” simply by gauging how you feel. Cues such as sweating, breathing patterns and aching muscles will help to gauge exercise intensity.
Twenty to 30 minutes per workout appears to be the minimum, although a few studies conducted with very low fit individuals have demonstrated gains with as little as 10 to 15 minutes. The ACSM recommends 20 to 60 minutes of continuous activity per exercise session. Note that the duration of exercise can also be prescribed in terms of distance covered or calories burned.
It is a common misconception that aerobic exercise benefits only the heart and circulatory system. Our muscles benefit as well, and the effect is very specific. Regular aerobic exercise improves the muscles ability to produce energy and utilize oxygen. Only those muscle fibers directly linked to the exercise are recruited for action, so improvements in aerobic fitness in response to one form of exercise won’t necessarily transfer in totality to another form of exercise. In practical terms this means that, to produce maximum results, the biker should bike and the runner should run.
Exercise volume reflects the total amount of physical activity in a workout and is dependent on the duration as well as the intensity of the exercise. Low intensity training, commonly referred to as LSD (long-slow-distance), emphasizes the quantity of exercise over the quality (intensity) of exercise. High intensity training requires greater effort but is of shorter duration where the training heart rate typically lies between 75 and 90 percent of HRmax. High intensity aerobic training also improves leg strength, leg speed and muscular endurance—all factors that can impact your time in 10K races. Some studies appear to show that similar gains can result in response to a shorter duration high-intensity program and a longer duration lower-intensity program. The most critical factor is matching the optimal threshold for duration with the appropriate exercise intensity.
Periodically, you will have to adjust your program to accommodate an improving level of aerobic fitness. Progression should be made in small increments by manipulating one or more of the FITT-VP factors. For example, you could increase the frequency from three to four workouts per week or increase the duration of each workout from 30 to 45 minutes. Regardless of how you do it, the progression should be gradual. Slow and steady wins the race.