Running Economy

In many sports, speed is essential, and improving speed is always sought after. To improve speed, you must increase the stride length or strike rate. Many athletes and coaches initially concentrate on improving stride length to find that both strike rate and speed decrease. It is more effective to work on strike rate because this increases the leg muscles' power, increasing stride length (Mackenzie 2004)^[1].

In several 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 a long-sustained burst of energy and oxygen consumption (breathing rhythm) must be effective and efficient.

Running economy can also be improved by developing your VO₂ max and vVO₂ max.

Stride Length and Rate

Exercise physiologists Jack Daniels, PhD monitored the athletes' strike rate and stride lengths in the 1984 Olympic track and field competitions. He found that competitors in the shorter distances had longer stride lengths. Female stride lengths varied from 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.

Stride length - 100m sprinter

Despite the differences in the athletes' abilities in each group, the results were somewhat similar. Work conducted by Hoffman (1971)^[2] 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 (1972)^[3] on the best twelve 100m sprinters (11.0 to 12.4 seconds) at Stanford University concluded that the standard stride length was 1.17 times the athlete's height. Despite the differences in the athletes' abilities in each group, the results were somewhat similar.

Further work conducted by Atwater (1973) 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 (1971) and Rompotti (1972)^[3] was conducted on cinder tracks. In contrast, 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 strike rate

To determine your strike rate, count the 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, make a conscious effort to increase the strike rate. To do this, concentrate on quicker, lighter, relaxed steps, but do not change how 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 by adjusting the stride length when running up hills by adjusting the stride length. If you let the 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: develop the hamstrings, gluteal and 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 an 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 an 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
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 minimal 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

The Breathing Issue

Most elite athletes use a 2-2 breathing rhythm. They breathe in for two steps, and they breathe out for two steps. The 2-2 breathing rhythm means taking 45 breaths (assuming you now have a strike rate of 90), which is slow enough to allow for a good depth of breathing. It is recommended to practice all kinds of breathing patterns to become familiar with them and note your body's reaction. Try the 3-3 breathing rhythm, 4-4 breathing rhythm, and unequal breathing rhythms such as 3-2 and 2-3 All the athletes I work with (except the sprinters) use a 2-2 or a 3-3 breathing rhythm. II use the 2-2 breathing rhythm, starting the left foot's breathing cycle. If you use the 2-2 breathing rhythm and experience stitch, switch the breathing rhythm to begin on the other foot or switch to a 3-3 breathing rhythm until the stitch subsides.

A 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. The critical point is that your breathing rhythm will tell you how hard you are working and allow you to control how hard you work.

Free Calculator

Stride Length Calculator - a free Microsoft Excel spreadsheet you can download and use on your computer.

References

MACKENZIE, B. (2004) Running Economy. Brian Mackenzie's Successful Coaching, 11 (ISSN 1745-7513) p. 13-15
HOFFMAN, K. (1971) Stature, leg length and stride frequency. Track Technique, 46, p. 1463-1469
ROMPOTTIE, K. (1972) A study of stride length in running. International Track and Field, p. 249-256

Page Reference

If you quote information from this page in your work, then the reference for this page is:

MACKENZIE, B. (1999) Running Economy [WWW] Available from: https://www.brianmac.co.uk/economy.htm [Accessed