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Running EconomyIn many sports speed is an important attribute and ways to improve speed are sought after. In a simplistic view, to improve speed you need to increase stride length and/or stride rate. Many athletes and coaches initially concentrate on improving stride length only to find that both stride rate and speed decrease. It is perhaps more effective to work on stride rate because this increases the power in the leg muscles which in turn naturally increase stride length. In a number of sports (e.g. football, basketball, netball, hockey) the athlete is required to conduct short bursts of effort and is then able to recover by getting oxygen back into the system. There are sports (e.g. running) where there is a long sustained burst of effort and oxygen consumption (breathing rhythm) needs to be effective and efficient. Running economy can also be improved by improving your vVO2max.
Stride Length and RateExercise physiologists Jack Daniels, PhD monitored the stride rate, stride lengths of the athletes in the 1984 Olympic track and field competitions. It was found that competitors in the shorter distances had longer stride lengths. Female stride lengths varied form 4 feet 10 inches in the marathon to 6 feet 8 inches for the 800 metres. Male stride length was 6 feet 2 inches during the 10 kilometre race to just over 7 feet 9 inches in the 800 metres. In contrast, the stride rate did not vary significantly. Stride rates for all events, for both men and women, fell between 185 and 200 steps per minute.
Stride length - 100m sprinterWork conducted by Hoffman on male 100 metre sprinters (10.4 to 11.0 seconds) indicated that the average stride length was 1.14 times the athlete's height. Similar work conducted by Rompotti on the best twelve 100m sprinters (11.0 to 12.4 seconds) at Stanford University concluded that the normal stride length was 1.17 times the athletes height. Despite the differences in abilities of the athletes in each group the results are fairly similar. Further work conducted by Atwater on twenty three 100m sprinters (9.9 to 10.4 seconds) concluded that the average stride length was 1.35 times the athlete's height. The possible reason for the differences in the results is that the work by Hoffman and Rompotti was conducted on cinder tracks; where as the work by Atwater was conducted on synthetic surfaces. Using Atwater's results, the six foot athlete (1.8 metres) has an average stride length of 2.5 metres. How to improve Stride RateThe easiest way to determine your strike rate is to count the number of times your right foot lands during one minute of running. Repeat the one minute runs at different speeds from an easy jog to interval speed. If you are like an elite athlete you will find that your stride rate is 90 or more per minute (180 steps) and is similar for various speeds. If your stride rate is less than 90 then make a conscious effort to increase the stride rate. To do this, concentrate on quicker, lighter, relaxed steps, but do not change the way your feet strike the ground. I have found that Aqua running often helps athletes with a slow strike rate. Cross country runners need to maintain strike rate when running up hills by adjusting the stride length. If you let strike rate slow down you will find that fatigue sets in and it is harder to get back to the desired strike rate once you are over the crest of the hill. Exercises to improve Stride Length and FrequencyPerform the following three exercises in the order in which they are presented. The high-bench step-up: develops the hamstrings, with complimentary development of the gluteals (the 'buttock' muscles) and the quadriceps.
One-leg squat: develops the quadriceps and gluteals, with a complimentary boost to the hamstrings.
One-leg hops in place: builds strength and coordination in the entire lower extremity, including the foot, ankle, shin, calf, thigh, and hip.
The Breathing IssueMost elite athletes use a 2-2 breathing rhythm. That is they breathe in for two steps and they breathe out for two steps. The 2-2 breathing rhythm means you are taking 45 breaths (assume you now have a strike rate of 90) which is slow enough to allow for good depth of breathing. It is recommended to practice all kinds of breathing patterns, just to become familiar with them and to note your body's reaction. Try the 3-3 breathing rhythm, 4-4 breathing rhythm and try unequal breathing rhythms such as 3-2 and 2-3. All the athletes I work with (except the sprinters) use either a 2-2 or a 3-3 breathing rhythm. I personally use the 2-2 breathing rhythm starting the breathing cycle on the left foot. If you use the 2-2 breathing rhythm and you experience stitch then switch the breathing rhythm to start on the other foot or switch to a 3-3 breathing rhythm until the stitch subsides. Long term analysis conducted by Jack Daniels has found that elite athletes in races up to and including the 10K use the 2-2 breathing rhythm at the start of the race and after completing about two-thirds of the race they switch to a 2-1 breathing rhythm. For races longer than 10k the 2-2 breathing rhythm is used for the whole distance, perhaps shifting to a 2-1 breathing rhythm in the last minute or two for the sprint finish. An important point is that your breathing rhythm will not only tell you how hard you are working but also allow you to control how hard you work. Free Calculator
Associated PagesThe following Sports Coach pages should be read in conjunction with this page:
Associated BooksThe following books provide more information related to this topic:
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