Trail Running Trekking Poles Dual-Pole Mechanics Decoded: Scientific Propulsion Techniques for Offloading 20% of Lower-Limb Work on Uphills and a Complete Guide to Cadence Synchronization

1. Introduction and Cutting-Edge Research Background

The development of trail running in Taiwan has evolved in recent years from a simple “runner traversing mountain paths” into an endurance science that places a high premium on “efficiency” and “economy.” Particularly in races featuring long, steep climbs—such as Yangmingshan Fengzhongjian, Zhenxibao, and Cilan Forest Road—we frequently observe a sharp increase in the proportion of elite trail runners using trekking poles. This is no longer the exclusive domain of older-generation hikers; rather, it has become an essential tool for contemporary elite runners to “distribute fatigue” and “maintain pace.”

From a review of the sports science literature, early research on trekking pole use in trail running focused largely on the effects of Nordic Walking on cardiorespiratory function. However, over the past five years, as pole usage has become widespread in European and American ultra races such as UTMB and Hardrock 100, the academic community has shifted its attention toward the quantitative relationship between “upper-limb muscle engagement” and “lower-limb joint loading.” A simulation study published in the European Journal of Applied Physiology indicated that on sections with a gradient greater than 15%, regular and rhythmically correct double-pole propulsion can significantly reduce the integrated electromyography (iEMG) values of the quadriceps while simultaneously improving stride stability.

Notably, the research trend after 2023 is no longer satisfied with the binary question of “does it work or not,” but rather delves further into “under different gradients and different fatigue states, which pole-planting rhythm achieves the best energy transfer efficiency.” Within this context, the comparison between alternating diagonal pole planting and simultaneous double poling has become a hot topic in the field of sports biomechanics.

2. Core Mechanisms of Exercise Physiology and Biomechanics

2.1 Physiological Basis of Upper-Limb Muscle Work

To understand how trekking poles share the load of the lower limbs, we must first establish the concept of “muscle synergy.” In steep uphill running without poles, the primary sources of propulsion are the knee extensors (quadriceps) and the ankle plantar flexors (gastrocnemius and soleus). As the gradient increases, the vertical displacement of the body’s center of mass grows, requiring the quadriceps to generate greater concentric contraction force to counteract gravity.

When trekking poles are introduced, an entirely new pathway opens in the kinetic chain. Through gripping the pole shaft, pressing the arms downward, and pushing backward, the latissimus dorsi and triceps brachii become the primary power-output muscle groups. The latissimus dorsi is responsible for pulling the humerus from a flexed position into extension, which precisely matches the backward-push trajectory of the pole; the triceps brachii is responsible for stabilizing the elbow joint at the end of the push, preventing energy loss due to joint laxity.

2.2 Derivation of the Torque Model for 20% Lower-Limb Work Sharing on Uphill Sections

We can simplify uphill running into a rigid-body model for mechanical derivation. Assume the runner’s body mass is ( m ), the gradient angle is ( \theta ), and the vertical displacement per step is ( h ). In the pole-free state, the net mechanical work ( W_{leg} ) that the lower-limb muscles must provide is approximately:

[
W_{leg} = m \cdot g \cdot h + \frac{1}{2} m \cdot v_{vert}^2
]

where ( g ) is the gravitational acceleration (9.81 m/s²) and ( v_{vert} ) is the change in vertical velocity of the body’s center of mass.

When using trekking poles, we introduce an “upper-limb assistive propulsion force” ( F_{pole} ), whose direction of action runs along the pole shaft axis, forming an angle ( \phi ) with the ground. At this point, the ground reaction force and the support force at the pole tip form a force-couple system, reducing the vertical support force required from the lower limbs. Through inverse dynamics calculations, when the pole-tip support force accounts for approximately 15% to 20% of body weight, and the push rhythm is synchronized with the contralateral foot-strike frequency, the total torque output of the hip, knee, and ankle joints can be reduced by approximately 18% to 22%. This is the mechanical basis for “sharing 20% of lower-limb work.”

2.3 Neuromuscular Control of Cadence Synchronization

Using trekking poles is not simply a matter of “hands move, feet move”; it involves the integration of limb rhythms by the central nervous system. Research has found that when the pole-planting frequency and cadence maintain an integer ratio of 1:1 or 2:1, neuromuscular coordination is optimal. If the pole rhythm and cadence fall into phase offset, not only is propulsion efficiency lost, but unnecessary oxygen consumption may also increase due to overlapping contraction timing between upper- and lower-limb muscles.

3. Field Testing and Comparative Analysis of Key Parameters

To present the differences between pole strategies more concretely, we have compiled data from relevant sports science literature and field tests, comparing alternating diagonal poling and simultaneous double poling across two typical gradients.

3.1 Data Comparison: Alternating Diagonal Poling vs. Simultaneous Double Poling

3.2 Data Analysis and Practical Implications

Two key phenomena can be observed from the table above:

1. On moderate gradients (10-15%): Alternating diagonal poling preserves a higher cadence and dynamic continuity, resulting in lower heart rate and oxygen uptake compared to simultaneous double poling. This is because the alternating pole pattern aligns more closely with the rotational inertia of running, allowing for smoother energy transfer.
2. On steep gradients (20-25%): The advantage of simultaneous double poling emerges. At this point, the runner needs “stable support” and “explosive instantaneous thrust.” Simultaneous double poling allows the upper-limb muscles to generate peak force in a short period, effectively sharing the load of the quadriceps. As a result, quadriceps EMG values are significantly lower than with alternating poling, and overall perceived exertion is also lower.

4. Periodized Training Plan and Equipment Adjustment Guide

4.1 Equipment Adjustment: The Science of Pole Length Setting

The length setting of trekking poles directly affects the lever arm and push efficiency. Generally speaking, on gentle terrain (gradient less than 5%), the pole length should be set so that the elbow joint bends at approximately 90 degrees. However, for the steep climbs commonly found in Taiwanese trail races (such as the East Route of Wuling or the Jiannan Road steep section of Fengzhongjian), it is recommended to shorten the pole length by 5 to 8 centimeters. This allows the pole tip to land precisely behind the projection point of the body’s center of mass when the body leans forward, ensuring that the backward thrust vector is effectively converted into forward momentum.

4.2 Periodized Training Plan (Four-Week Adaptation Period)

The following plan is suitable for runners with basic trail running ability who are preparing to use trekking poles in competition:

5. Race Nutrition, Environmental Adaptation, and Race-Day Strategy

5.1 Carbohydrate Supplementation Strategy with Upper-Limb Muscle Engagement

When upper-limb muscles are heavily involved in propulsion, overall energy expenditure increases by approximately 8% to 12% compared to lower-limb-only exercise. This means that in long-distance races such as UTMB or the Around Hualien-Taitung circuit, you must recalculate your hourly carbohydrate intake. It is recommended to increase the hourly carbohydrate target from the typical 60 grams to 70 to 80 grams, alternating between “liquid nutrition + solid food” to reduce gastrointestinal burden. For example: consume 150 ml of sports drink (approximately 20 grams of carbohydrates) every 30 minutes, paired with one energy gel (approximately 25 grams of carbohydrates) and half a banana (approximately 15 grams of carbohydrates) every hour.

5.2 Hydration and Electrolyte Balance

Using trekking poles increases heat production in the upper limbs and core muscles, particularly in high-humidity, muggy environments like Yangmingshan, where sweat loss rates can reach 1.5 to 2 liters per hour. It is recommended to conduct a sweat-rate test before the race, replenish 150 to 200 ml of fluid every 15 minutes during competition, and supplement 500 to 800 mg of sodium per hour to maintain neuromuscular excitability.

5.3 Race-Day Strategy: Gradient Response for Wuling and Fengzhongjian

Taking Taiwan’s classic “East Route Wuling” (Dayuling to Wuling, average gradient approximately 8%, steepest section reaching 15%) as an example, it is recommended to decisively switch to simultaneous double-poling mode on sections exceeding 10% gradient, deliberately lowering cadence to approximately 150 spm to gain a longer push duration per step. For courses with dramatic gradient fluctuations like Yangmingshan Fengzhongjian, alternating diagonal poling should serve as the primary rhythm, reserving simultaneous double poling as the “explosive tool” for conquering steep sections.

6. Common Operational Mistakes and Scientific Myth-Busting

6.1 Myth: Trekking Poles Will Make Me Slower?

This is a common misconception. Experimental data shows that on sections with a gradient greater than 15%, runners using trekking poles correctly achieve vertical speeds approximately 5% to 8% higher than unassisted runners. However, on gentle sections or descents, poles can indeed slow you down due to added weight and swing inertia. Therefore, the key lies in judging the “course gradient structure” and “timely stowing.”

6.2 Mistake: Should I Press “Downward” with My Arms to Generate Propulsion?

This is a serious biomechanical error. Pressing downward creates an upward reaction force on the body, increasing vertical oscillation of the center of mass and wasting energy. The correct force direction is to “push backward and downward,” decomposing the force vector along the body’s forward direction of travel. Imagine pushing the pole tip backward to “shove the ground away,” rather than “driving it into” the ground.

6.3 Mistake: The Faster the Cadence, the Higher the Pole Efficiency?

The “synchronization” between cadence and pole-planting frequency is far more important than “absolute speed.” If cadence is too fast and causes chaotic pole rhythm, upper- and lower-limb muscle contractions will interfere with each other—a phenomenon medically termed “muscle co-contraction”—which significantly increases oxygen consumption. It is recommended to maintain cadence within your personal comfort zone (typically 155-170 spm) and ensure that the pole-tip plant moment completely overlaps with the contralateral heel-strike moment.

6.4 Mistake: Can Trekking Poles Completely Replace Lower-Limb Strength Training?

Trekking poles merely “share” rather than “replace” lower-limb work. Over-reliance on poles can lead to “use it or lose it” atrophy of lower-limb muscles, ultimately reducing proprioception and ankle joint stability over the long term. In your training plan, you should still retain at least one pole-free steep-climb session per week to maintain baseline lower-limb strength and neural recruitment capacity.

7. Expert FAQ

Q1: Should I use folding poles or fixed-length poles in a race?

This depends on course characteristics and personal stowing habits. Folding poles (such as Z-type or three-section poles) are convenient to stow in a backpack at transition zones or on gentle sections, making them well-suited for races with paved-road segments like IRONMAN 70.3 Kenting. Fixed-length poles offer better structural rigidity and force transfer efficiency, making them suitable for pure trail races with continuous climbs and no frequent stowing needs, such as the Alpine routes of UTMB. If budget permits, it is recommended to prepare both and choose based on course type.

Q2: How should I adjust my breathing rhythm when using trekking poles?

When performing simultaneous double poling, the bracing of the upper body (core tightening) temporarily compresses thoracic volume. It is recommended to inhale just before the pole tips contact the ground and exhale during the push phase. This aligns with the “exhale on exertion” principle of weight training, preventing excessive blood pressure fluctuations and ensuring a continuous oxygen supply.

Q3: What recommendations do you have for pole tips in Taiwan’s humid and rainy environment?

Taiwan’s mountain areas (such as Beihong and Jinshuiying Historic Trail) often feature slippery rock slabs and humus soil. It is recommended to choose models with tungsten carbide pole tips, whose hardness and grip far exceed standard steel tips. If the course includes substantial asphalt or hard surfaces, rubber tip covers should be attached to prevent slipping and reduce instantaneous impact on the joints.

Q4: How can I avoid numbness in the forearms and palms from prolonged pole use?

Forearm numbness typically stems from “excessive gripping” and “excessive carpal tunnel pressure.” Be sure to use grips with comfortable straps and learn to partially hang body weight on the straps rather than relying entirely on finger grip strength. Every 20 to 30 minutes, perform a one-handed release and arm swing to promote blood circulation in the forearms.

Q5: For runners new to trail running, when is the best time to introduce trekking poles?

It is recommended to introduce trekking poles only after accumulating at least 3 months of trail running experience with 2 or more sessions per week. Introducing them too early can foster incorrect movement patterns of “relying on the upper body to pull the body along,” while neglecting the stabilizing function of the core muscles and the gluteus medius. Beginners should first practice technique on gentle riverside park terrain, and only enter mountain trails after movement patterns are stable.