There are three important physiological determinants of better running performance; VO2 Max (maximal oxygen uptake), lactate threshold and running economy. Improvements in one or more of these aspects can improve running performance efficiency, enabling a runner to cover a given distance at a faster pace without using more energy to do so. Obviously such improvements are a desirable outcome of running training. Here the focus of discussion is on improving running economy.
As defined in a paper by Mark Steinle and Stephen Baker, “The Science Behind Training,” accessed 04 Sept. 2016 at tonezonerunners.org, “running economy is a physiological measure of the amount of oxygen required to run at a specific pace.” The less oxygen required to run at a specific pace the better a runner’s running economy.
Those interested in improving running economy would likely be interested in understanding the variables that influence running efficiency or economy. This would allow for determining which of those variables might be subject to manipulation through training so that running performance efficiency might be enhanced.
An article by researcher Philo Saunders, “Reliability and Variability of Running Economy in Elite Distance Runners,” published in Medicine & Science in Sports & Exercise, the official journal of the American College of Sports Medicine, provides a list of the biomechanical motion factors that contribute to optimal running economy and better running performance, summarized here:
height of the runner (slightly shorter than average for males, slightly taller than average for females)
ectomorphic physique (thin, long-limbed, shoulders and hips of similar width)
low percentage of body fat
majority of leg weight distributed closer to the hips (larger quads, smaller calves)
smaller than average feet
optimal stride length for the individual (absence of either over-striding or under-striding)
low vertical oscillation (minimal wasted up and down movement while running)
minimal arm movement
acute bending of the trail leg during the swing phase (i.e., with the right foot planted and the left leg catching up and coming through it is better to have the left leg fully bent rather than straight)
running shoes that are light-weight but cushioned.
As can be seen, a number of the factors are genetically determined and not subject to manipulation (e.g., height, morphology, foot size, pelvis width). Two physical characteristics; body fat percentage and size relationship between the quads and calves are subject to some modification through diet and strength training. Optimal foot wear of course can be selected. Four of the factors listed are potentially subject to enhancement through running training; stride length, vertical oscillation, arm movement and trail leg angle.
Expert Tips for Improving Running Efficiency
For distance runners, the physiological factors that offer the most promise when it comes to improving running economy through training are stride length, vertical oscillation and arm movement. All of these are related to the concept running form.
Running economy begins with efficient running form according to Jeff Galloway, 1972 American Olympic distance runner and author of Galloway’s Book on Running (Shelter Publications. Boinas, CA). Galloway recommends an upright running posture with the chest up and out and hips forward. This he says keeps the hips properly aligned directly beneath the head and shoulders. Running with a slight forward or backward lean he notes wastes energy as the runner is required to overcome gravity with every step to maintain balance. Galloway recommends runners work on form twice each week by running form accelerations on a slight downhill incline.
Speed sessions, according to running coach Jack Daniels, author of Daniel’s Running Formula (Human Kinetics. Champagne, IL) are valuable for improving running economy. Daniels believe that running repetitions at or near race pace help runners learn to eliminate unnecessary arm and leg motions and to learn to feel comfortable running at faster speeds.
In her article, “The Perfect Form,” published in the Runner’s World magazine, Jane Unger Hahn adds further emphasis to the advice of Galloway and Daniels with some more direct tips on running form. Noting that head position is the key to overall running posture she recommends that runners keep their gaze up, scanning the horizon to keep the neck and back in proper alignment.
Shoulders, Hahn says, should be low and loose. She adds that runners need to guard against the natural tendency to lift and tighten the shoulders when feeling fatigued. The arms, Hahn says should bent at about a 90-degree angle and should swing back and forth between waist and lower-chest level to work in concert with leg stride in driving the body forward.
Hahn’s article also addresses the importance of stride length to running economy. Distance runners she observes do not need the exaggerated knee lift used by sprinters. Instead endurance running is most efficient with slight knee lift, quick turnover and a short stride that has the feet striking directly beneath the body with each step to avoid wasting energy. With an efficient stride, issues with vertical oscillation are generally avoided.
Someone once observed that great runners are born and then trained, acknowledging that some are simply genetically predisposed to running more economically than others. Yet just as about anyone can learn to become a runner, in the same way, focusing on form, posture and stride can help any runner can improve in running efficiency, causing better running performance.