Running Economy: Ten Key Factors That Affect Running Efficiency

Introduction

In running physiology, there is an indicator that predicts long-distance running performance better than maximal oxygen uptake (VO2max)—Running Economy (RE). It is defined as the oxygen consumption (mL/kg/min) required to sustain aerobic running at a given speed; the lower the value, the more economical and efficient the running. Research shows that two runners with the same VO2max can differ by 10% in running economy, resulting in a nearly 20-minute difference in marathon performance. So, what determines running economy?

How Running Economy Is Measured

Standard measurement is conducted on a laboratory treadmill: the subject runs steadily at several submaximal intensities (e.g., 60–80% of VO2max), while a gas analyzer measures oxygen consumption, which is then normalized by body weight to obtain oxygen uptake per kilogram per minute. In general:

Ten Key Factors That Affect Running Economy

1. Footstrike Pattern and Impact Forces

The braking force generated by a heel strike adds extra energy expenditure to “counteract” one’s own forward momentum. Midfoot or forefoot striking offers better braking-force control and can theoretically improve RE by about 1–3%.

2. Vertical Oscillation

As mentioned earlier, excessive vertical displacement means energy is used for “bouncing upward” rather than “moving forward.” Research shows that for every 1 cm reduction in vertical oscillation, running RE can improve by about 1%.

3. Tendon Elastic Energy Storage (Especially the Achilles Tendon)

Efficient use of elastic energy storage in the Achilles tendon and plantar fascia is one of the key reasons elite African distance runners excel in running economy. Tendon stiffness training (plyometrics) can enhance this ability.

4. Muscle Fiber Composition

Slow-twitch fibers (Type I) are more efficient at aerobic speeds than fast-twitch fibers (Type II). Those with a naturally higher proportion of slow-twitch fibers (such as East African distance runners) often have an inherent RE advantage. Although training cannot fundamentally alter muscle fiber ratios, long-term aerobic training can increase mitochondrial density in slow-twitch fibers.

5. Body Weight and Body Fat

RE is calculated per kilogram of body weight, so reducing body weight—especially unnecessary fat—can directly improve RE. For every 1 kg lost, oxygen consumption at the same speed decreases by approximately 1–1.5 mL/kg/min in RE value. However, excessive dieting that reduces muscle mass can be counterproductive.

6. Training Volume and Years of Experience

Long-term endurance training improves RE through multiple mechanisms:

• Increased mitochondrial density (more efficient aerobic metabolism)
• Increased proportion of slow-twitch fibers
• Improved neuromuscular coordination (more economical movement)
• Tendon stiffness adaptation

In general, the more cumulative training mileage a runner has, the better their RE, and this improvement can persist for years.

7. Shoe Selection

Carbon-plated running shoes (such as the Nike Vaporfly and Adidas Adizero Adios Pro) have been confirmed by multiple studies to directly improve RE by about 3–5%. For every 100 grams of shoe weight reduced, RE improves by about 0.5–1%.

8. Running Posture Efficiency (Cadence, Arms, Forward Lean)

The combined effect of all good running form elements—appropriate cadence, correct arm swing, and moderate forward trunk lean—constitutes postural efficiency. These factors are difficult to quantify individually, but together they can contribute a 2–5% improvement in RE.

9. Warm-Up and Temperature

Muscles contract most efficiently in a warm state (core temperature around 38.5°C). A proper warm-up (10–15 minutes) enhances neuromuscular efficiency and improves immediate RE performance. In cold environments (winter road running in Taiwan), RE is initially poorer and gradually improves as body temperature rises.

10. Altitude Training Adaptation

Performing 4–6 weeks of altitude training at 2,000–3,000 meters can increase hemoglobin concentration and red blood cell oxygen-carrying efficiency. Within about 2–4 weeks after returning to low altitude, athletes can often run faster at the same oxygen uptake, with RE improvements reaching 3–5%. This is also the fundamental reason many international marathoners undergo altitude training before major races.

Comprehensive Training Recommendations for Improving Running Economy

1. Add one strength training session per week: Compound movements targeting the calves, glutes, and core. Research shows that 8–12 weeks of resistance training can improve RE by about 2–4%.
2. Progressively increase mileage: Keep weekly mileage increases to no more than 10% to give the neuromuscular system time to adapt.
3. Incorporate plyometric training: One to two sessions per week of jump rope, box jumps, or lunge jumps can significantly enhance tendon elasticity within 6–8 weeks.
4. Diversify training paces: Mix easy runs, tempo runs, and intervals to target different energy systems and movement patterns.
5. Conduct regular technique assessments: Film and analyze your running form every 2–3 months to confirm improvement in each metric.

Conclusion

Running economy is the most comprehensive efficiency indicator in running science, integrating all the influences of physiology, biomechanics, training adaptation, and equipment. For Taiwanese runners, the most worthwhile priorities are: systematic strength training, running form optimization, and accumulating sufficient mileage. While these may not produce immediate results like buying a pair of carbon-plated shoes, the improvements they bring are truly your own ability—they won’t disappear when you take off your running shoes.

Related Reading

• Running Economy Quantified: Using Data to Assess Your Running Economy
• Running Economy: The Secret to Running Faster with Less Energy
• Measuring and Improving Running Economy
• The Science of Running Economy: How to Run Faster with Less Energy