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Exercise physiologists Jack Daniels, Ph.D. monitored the strike rate and stride lengths of athletes in the 1984 Olympic track and field competitions. He 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 in the 10-kilometre race to just over 7 feet 9 inches in the 800 metres. He found that the strike rate did not vary significantly. Strike rates for all events (male and female) fell between 185 and 200 steps per minute.
Reference: Hoffman, K (1971). Stature, leg length and stride frequency. Track Technique, 46: 1463-69.
Reference: Rompottie, K (1972). A study of stride length in running. International Track and Field. (pp.249-56)
According to Jack Daniels in Running Formula:
I find that very few (sometimes none out of a class of 25 or 30) take as many as 180 steps per minute. In fact, some turn over as slowly as 160 steps per minute. The main disadvantage of this slower turnover is that the slower you take steps, the longer you spend in the air, and the longer you’re in the air, the higher you displace your body mass and the harder you hit the ground on landing. When you consider that many running injuries are the result of landing shock, it’s not surprising that experienced runners tend to turn over faster than beginning runners do.
How to improve strike rate
To determine your strike rate count the number of times your right foot lands during one minute of running. Repeat these one-minute runs at different speeds. If you are like an elite athlete you will find that your strike rate is 90 or more per minute (180+ steps) and is similar for various speeds. If your strike rate is less than 90 then make a conscious effort to increase the strike 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 their 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 Frequency
Perform the following three exercises in the following order:
The high-bench step-up: develops the hamstrings, gluteals and the quadriceps.
Begin from a standing position on top of a bench (approximately knee height), with your body weight on your left foot and your weight shifted toward the left heel
The right foot should be free and held slightly behind the body
Lower the body in a controlled manner until the toes of the right foot touch the ground, but maintain all of your weight on the left foot
Return to the starting position by driving downward with the left heel and straightening the left leg
Repeat for the prescribed number of repetitions, and then switch over to the right leg
Maintain absolutely upright posture with the trunk throughout the entire movement, with your hands held at your sides (with or without dumbbells)
Frequency: 2 to 3 times a week - 2 to 3 sets of 15 to 20 repetitions - 2 to 3 minutes recovery
One-leg squat: develops the quadriceps and gluteals and hamstrings.
Stand with the left foot forward and the right foot back, with the feet about one shin-length apart (your feet should be hip-width apart from side to side)
Place the toes of the right foot on a block or step that is six to eight inches high. As in the step-up exercise, most of the weight should be directed through the heel of the left foot
Bend the left leg and lower the body until the left knee reaches an angle of 90 degrees between the thigh and lower leg
Return to the starting position, maintaining upright posture with the trunk and holding your hands at your sides
Complete the prescribed number of repetitions with the left leg before switching to the right leg
Frequency: 2 to 3 times a week - 2 to 3 sets of 15 to 20 repetitions - 2 to 3 minutes recovery
One-leg hops in place: builds strength and coordination in the entire lower extremity, including the foot, ankle, shin, calf, thigh, and hip.
Start from the same position you used for the one-leg squat, with the toes of the right foot supported by a six to eight inch block
Hop rapidly on the left foot at a cadence of 2.5 to 3 hops per second (25 to 30 foot contacts per 10 seconds) for the prescribed time period
The left knee should rise about four to six inches, while the right leg and foot should remain stationary
The left foot should strike the ground in the area of the mid-foot and spring upwards rapidly - as though it were contacting a very hot plate on a cooker
The hips should remain level and virtually motionless throughout the exercise, with very little vertical displacement.
After hopping for the indicated time on the left leg, switch to the right leg and repeat the exercise
Frequency: 2 to 3 times a week - 1 to 2 sets of 10 to 20 seconds - 2 to 3 minutes recovery
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