Running: Finding Your Most Efficient Speed and Improving Performance

What is the most efficient speed to run at?

The "most efficient speed" for running is not a universal constant but rather an individually optimal pace that minimizes energy expenditure for a given distance or maximizes performance for a specific goal, heavily influenced by an individual's unique physiology, biomechanics, and training adaptations.

Understanding Running Efficiency

Running efficiency, often referred to as running economy (RE), is a measure of the oxygen cost (energy expended) at a given submaximal running speed. A more efficient runner uses less oxygen (and thus less energy) to maintain the same pace as a less efficient runner. This concept is crucial for endurance performance, as it directly impacts how long a runner can sustain a particular speed before fatigue sets in. It's not about being the fastest, but about being the most economical with your energy resources.

The Concept of "Preferred Running Speed" (PRS)

Research consistently shows that individuals naturally gravitate towards a preferred running speed (PRS) when given the freedom to choose their pace. This PRS is often the speed at which their physiological cost of transport (energy expenditure per unit distance) is minimized. While it feels most comfortable, it may not always align with the optimal speed for specific training adaptations or race performance. However, deviations from this preferred speed often lead to increased metabolic cost.

Physiological Determinants of Efficiency

Several physiological factors contribute to an individual's running efficiency:

• Aerobic Capacity (VO2max): While not a direct measure of efficiency, a higher VO2max (the maximum amount of oxygen an individual can utilize during intense exercise) allows a runner to sustain a higher percentage of their maximum oxygen uptake for longer, indirectly supporting more efficient running at higher speeds.
• Lactate Threshold: This is the highest running speed or exercise intensity that can be maintained without a continuous rise in blood lactate concentration. Running just below or at this threshold is often considered the most efficient pace for prolonged endurance efforts, as it balances speed with sustainable energy production.
• Running Economy (RE): As mentioned, this is the direct measure of how much oxygen a runner consumes at a given submaximal speed. It's a key predictor of endurance performance, often more so than VO2max among elite athletes.
• Muscle Fiber Type Distribution: Individuals with a higher percentage of slow-twitch muscle fibers tend to be more efficient at endurance running due to their greater oxidative capacity and fatigue resistance.
• Mitochondrial Density: Higher mitochondrial density within muscle cells improves the efficiency of aerobic energy production, reducing reliance on less efficient anaerobic pathways.

Biomechanics and Efficiency

Optimal running form plays a significant role in minimizing energy waste and maximizing efficiency. Key biomechanical elements include:

• Stride Length vs. Stride Rate (Cadence): While there's no single "ideal" cadence, most elite runners exhibit a high stride rate (typically 170-180+ steps per minute). A higher cadence, combined with a shorter stride, often leads to less vertical oscillation, reduced braking forces, and a more efficient use of elastic energy from tendons and muscles. Overstriding (too long a stride) is a common cause of inefficiency.
• Ground Contact Time: Shorter ground contact time is generally associated with more efficient running, as it minimizes the time spent absorbing impact and maximizes the time spent propelling forward.
• Vertical Oscillation: Excessive up-and-down movement wastes energy that could be used for forward propulsion. Efficient runners exhibit minimal vertical bounce.
• Running Form:
  • Posture: Tall, slightly forward lean from the ankles.
  • Arm Swing: Relaxed, elbows bent at 90 degrees, swinging forward and back, not across the body.
  • Foot Strike: Midfoot strike is often considered most efficient, allowing for optimal use of the foot's natural spring. Heel striking can introduce braking forces, while forefoot striking without proper mechanics can overstress calves.

Goals Dictate "Efficient" Speed

The "most efficient" speed is also highly dependent on your running goal:

• Endurance Running (e.g., Marathon Training): The most efficient speed for long distances is typically a sustainable, sub-maximal pace that can be maintained for hours. This often correlates with a pace at or just below your aerobic threshold or ventilatory threshold 1 (VT1), where fat is the primary fuel source and lactate accumulation is minimal. For race day, the goal pace might push slightly higher, closer to your lactate threshold.
• Tempo Runs/Middle-Distance Training: These runs aim to improve your lactate threshold. The "efficient" speed here is one that is challenging but sustainable for 20-60 minutes, pushing your physiological limits to adapt. This is often around your ventilatory threshold 2 (VT2) or lactate threshold.
• Speed Work/Interval Training: For short, high-intensity efforts, "efficiency" shifts from energy conservation to maximizing power output and speed. While biomechanical efficiency is still important to prevent injury and maximize force transfer, the metabolic cost is very high, relying heavily on anaerobic pathways.

How to Improve Running Efficiency

Improving your running efficiency is a multifaceted process that involves both physiological adaptations and biomechanical refinements:

• Strength Training: Focus on exercises that build power and stability in the glutes, hamstrings, quadriceps, and core. Plyometrics (jump training) are particularly effective for improving elastic energy return and reducing ground contact time.
• Running Drills and Form Work: Incorporate drills like A-skips, B-skips, high knees, butt kicks, and strides into your warm-up to reinforce proper mechanics, improve coordination, and increase stride rate.
• Varying Paces: Regularly include different types of runs – easy runs, tempo runs, interval training, and long runs – to train different energy systems and improve your body's ability to adapt to various speeds efficiently.
• Consistent Training Volume: Regular, progressive training builds endurance, strengthens muscles, and improves the cardiovascular system, all contributing to better efficiency over time.
• Cadence Drills: Use a metronome or a running watch with a cadence feature to gradually increase your stride rate, aiming for shorter, quicker steps.
• Proper Footwear: Ensure your running shoes are appropriate for your foot type and running mechanics, providing adequate cushioning and support to reduce impact and promote efficient movement.

Individual Variation and Testing

It's crucial to remember that there is no single "most efficient speed" that applies to everyone. What's efficient for an elite marathoner will be vastly different from what's efficient for a recreational runner. Physiological testing, such as VO2 max testing with lactate threshold analysis or running economy assessments conducted in a lab setting, can provide precise data on an individual's optimal physiological zones and help tailor training programs for maximum efficiency.

Ultimately, the most efficient speed is the one that allows you to achieve your specific running goals with the least amount of wasted energy and the highest sustainable performance, taking into account your unique physiological and biomechanical profile.