Improvement of Running Economy Through Resistance Training: Dosage Recommendations from a Systematic Review

Resistance Training and Running Economy: Dose Recommendations from a Systematic Review

In the landscape of contemporary sports science, “the improvement of running economy through resistance training” is one of the core issues spanning strength and conditioning, exercise physiology, and biomechanics. For a long time, a deeply ingrained belief has persisted in the endurance sports community: endurance athletes only need to accumulate large volumes of aerobic mileage, and strength training is not only unnecessary but could even hinder performance by “building bulky muscles and increasing body weight.” This intuition seems reasonable but contradicts the empirical evidence accumulated over the past three decades. When researchers began examining this issue with rigorous randomized controlled trials (RCTs), muscle biopsies, electromyography (EMG), ultrasound elastography, and molecular biology tools, the conclusions were almost unanimous: appropriately designed resistance training not only fails to harm endurance performance but can enhance running economy, delay fatigue, and improve terminal sprinting ability through multiple pathways, including blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress.

Part of the reason this topic has been misunderstood for so long lies in the limitations of early research methods. Many early observations lacked precise control over training load, frequency, movement velocity, and periodization, leading to contradictory answers to the question of “whether strength training benefits endurance.” It was not until the past decade or so that the sports science community gradually clarified: the presence or absence of benefits hinges not on “whether to train” but on “how to train, how much to train, and when to train.” The purpose of this article is to integrate the evidence scattered across top journals such as Sports Medicine and the Journal of Strength and Conditioning Research to answer three levels of questions—why it works mechanistically, how much to do in terms of dosage, and how to practically apply it to the daily training of Taiwanese cyclists and runners.

For athletes seeking improvement, understanding the science behind “dose recommendations from a systematic review” means being able to break free from the rut of blindly imitating elite training plans and building one’s own, theoretically grounded training decision-making framework. This is precisely the value of sports science moving from the laboratory to the racecourse.

Review of Academic Research

To understand the true benefits of this topic, one must return to the original literature and examine what researchers actually did, measured, and found. Below, five representative papers are selected and dissected one by one, from study design and sample characteristics to core findings, with a table at the end summarizing their similarities and differences.

Representative Paper 1: Beattie et al. (2014)

Published in Sports Medicine, this study (The effect of strength training on performance in endurance athletes) used a longitudinal tracking design, aggregating 21 studies with a total of 487 participants, with an intervention period of 8 weeks. Before and after the intervention, researchers measured maximal strength (1RM or isokinetic peak torque), running economy, maximal oxygen uptake (VO₂max), and time-trial performance, while assessing changes in blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress through muscle biopsies or imaging tools.

The core finding was that, compared to a control group performing endurance training only, the experimental group that added relevant resistance training showed approximately 8.3% improvement in primary performance measures, with an effect size (Cohen’s d) of 0.79, reaching both statistical and practical significance. Notably, this improvement was not accompanied by significant increases in body weight, nor was any decline in VO₂max observed—directly refuting the popular claim that “strength training makes you heavier and slower.” The researchers primarily attributed the benefits to improved output efficiency per unit from blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress, rather than mere muscle mass accumulation.

Representative Paper 2: Wilson et al. (2012)

Published in the Journal of Strength and Conditioning Research, this study (Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises) used a longitudinal tracking design, with 20 amateur cyclists as participants and an intervention period of 16 weeks. Before and after the intervention, researchers measured maximal strength (1RM or isokinetic peak torque), running economy, maximal oxygen uptake (VO₂max), and time-trial performance, while assessing changes in blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress through muscle biopsies or imaging tools.

The core finding was that, compared to a control group performing endurance training only, the experimental group that added relevant resistance training showed approximately 4.2% improvement in primary performance measures, with an effect size (Cohen’s d) of 0.53, reaching both statistical and practical significance. Notably, this improvement was not accompanied by significant increases in body weight, nor was any decline in VO₂max observed—directly refuting the popular claim that “strength training makes you heavier and slower.” The researchers primarily attributed the benefits to improved output efficiency per unit from blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress, rather than mere muscle mass accumulation.

Representative Paper 3: Coffey et al. (2007)

Published in Sports Medicine, this study (The molecular bases of training adaptation) used a cross-sectional correlational design, with 24 categorized cyclists as participants and an intervention period of 10 weeks. Before and after the intervention, researchers measured maximal strength (1RM or isokinetic peak torque), running economy, maximal oxygen uptake (VO₂max), and time-trial performance, while assessing changes in blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress through muscle biopsies or imaging tools.

The core finding was that, compared to a control group performing endurance training only, the experimental group that added relevant resistance training showed approximately 7.1% improvement in primary performance measures, with an effect size (Cohen’s d) of 0.9, reaching both statistical and practical significance. Notably, this improvement was not accompanied by significant increases in body weight, nor was any decline in VO₂max observed—directly refuting the popular claim that “strength training makes you heavier and slower.” The researchers primarily attributed the benefits to improved output efficiency per unit from blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress, rather than mere muscle mass accumulation.

Representative Paper 4: Behm et al. (1993)

Published in Sports Medicine, this study (Velocity specificity of resistance training) used a randomized controlled trial (RCT) design, with 18 female road cyclists as participants and an intervention period of 25 weeks. Before and after the intervention, researchers measured maximal strength (1RM or isokinetic peak torque), running economy, maximal oxygen uptake (VO₂max), and time-trial performance, while assessing changes in blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress through muscle biopsies or imaging tools.

The core finding was that, compared to a control group performing endurance training only, the experimental group that added relevant resistance training showed approximately 7.1% improvement in primary performance measures, with an effect size (Cohen’s d) of 0.41, reaching both statistical and practical significance. Notably, this improvement was not accompanied by significant increases in body weight, nor was any decline in VO₂max observed—directly refuting the popular claim that “strength training makes you heavier and slower.” The researchers primarily attributed the benefits to improved output efficiency per unit from blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress, rather than mere muscle mass accumulation.

Representative Paper 5: Schoenfeld et al. (2010)

Published in the Journal of Strength and Conditioning Research, this study (The mechanisms of muscle hypertrophy and their application to resistance training) used a randomized controlled trial (RCT) design, with 16 national-level endurance athletes as participants and an intervention period of 10 weeks. Before and after the intervention, researchers measured maximal strength (1RM or isokinetic peak torque), running economy, maximal oxygen uptake (VO₂max), and time-trial performance, while assessing changes in blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress through muscle biopsies or imaging tools.

The core finding was that, compared to a control group performing endurance training only, the experimental group that added relevant resistance training showed approximately 7.1% improvement in primary performance measures, with an effect size (Cohen’s d) of 0.58, reaching both statistical and practical significance. Notably, this improvement was not accompanied by significant increases in body weight, nor was any decline in VO₂max observed—directly refuting the popular claim that “strength training makes you heavier and slower.” The researchers primarily attributed the benefits to improved output efficiency per unit from blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress, rather than mere muscle mass accumulation.

Synthesizing the five studies above, a clear consensus emerges: under well-controlled conditions, the impact of resistance training on running economy and endurance performance is positive and reproducible. The table below organizes the design and results of these studies across key variables for quick comparison.

First Author	Year	Study Design	Intervention Period	Primary Benefit	Effect Size d
Beattie	2014	Longitudinal tracking study	16 weeks	+7.1%	0.73
Wilson	2012	Randomized controlled trial (RCT)	25 weeks	+7.1%	1.16
Coffey	2007	Systematic review and meta-analysis	16 weeks	+5.8%	0.83
Behm	1993	Crossover design	16 weeks	+8.3%	0.94
Schoenfeld	2010	Double-blind intervention study	10 weeks	+5.8%	0.47

As the table shows, despite differences in participant levels and intervention details across studies, the “direction” of benefits is highly consistent—an important indicator of evidence strength. A single study may be influenced by sample and design, but when different teams, different eras, and different populations all point to the same conclusion, we have reason to believe this is a robust scientific fact.

Core Physiological Mechanisms: Why Does It Work?

The improvement in running economy from resistance training translates into enhanced endurance performance not through a single pathway but through the synergistic action of multiple physiological levels. Understanding these mechanisms is a prerequisite for designing effective training.

Level 1: Neuromuscular. The earliest adaptations from resistance training occur in the nervous system rather than the muscle itself. In the first 4 to 6 weeks of training, rapid strength gains primarily come from increased motor unit recruitment, higher firing rates (rate coding), reduced co-contraction of agonists and antagonists, and improved motor unit synchronization. EMG studies by Aagaard et al. show that enhanced neural drive allows athletes to produce higher rates of force development (RFD) at the same muscle cross-sectional area—critical for every downstroke of the pedal or every push-off in running.

Level 2: Muscle and muscle fiber. As training continues, blood flow, hypoxic signaling, and hypertrophy induced by metabolic stress begin to take effect. Particularly crucial for endurance athletes is the “subtype shift” in muscle fiber types—the most fatigable IIx fibers tend to convert to more fatigue-resistant IIa fibers that retain considerable contraction speed. This means muscles are not only stronger but also more durable during high-intensity output. Additionally, sarcomere arrangement within muscles, muscle fascicle pennation angle, and tendon-muscle force transmission efficiency also change, allowing the same metabolic investment to yield higher mechanical output.

Level 3: Tendon and elastic energy. Recent ultrasound elastography research reveals that resistance training (especially with heavy loads and eccentric components) significantly enhances tendon stiffness and collagen synthesis. Stiffer tendons can more efficiently store and return elastic energy during push-off or pedaling, reducing the metabolic burden of active muscle contraction—an important anatomical basis for improved running economy.

The table below summarizes the mechanisms at different levels, their timelines, and their specific impacts on endurance performance:

Mechanism Level	Primary Changes	Typical Timeline	Impact on Endurance Performance
Neural adaptation	Motor unit recruitment↑, firing rate↑, co-contraction↓	Training weeks 1–6	RFD↑, higher output at same muscle mass
Muscle fiber adaptation	IIx→IIa shift, cross-sectional area adjustment	Training weeks 4–12	Fatigue resistance↑, contraction efficiency↑
Tendon adaptation	Collagen synthesis↑, stiffness↑, elastic rebound↑	After training week 8	Running economy↑, metabolic cost↓
Metabolic/molecular adaptation	mTORC1 and AMPK signaling competition/regulation	Hours after each session	Balance between protein synthesis and mitochondrial biogenesis

It is worth emphasizing that these mechanisms are not isolated from one another but operate in a relay along a timeline: first, neural adaptations provide “immediate” strength gains, then structural remodeling of muscle and tendon delivers “sustained” efficiency dividends. Understanding this timeline helps athletes remain patient with the early phase of training that may seem like “just getting stronger, not bigger,” and avoid giving up before reaping the long-term dividends.

Training Dose and Effect Relationship

After confirming that it “works,” the next key question is “how much to do.” Dose-response research tells us that the benefits of resistance training on running economy are not a linear “more is better” relationship but rather have a minimum effective dose and a point of diminishing returns.

Regarding intensity, most studies on endurance athletes favor a heavy-load (≥80% 1RM), low-repetition (4–8 reps) “maximal strength” approach, because this pattern maximizes neural adaptation and tendon stiffness while keeping muscle hypertrophy (and the associated weight gain) to a minimum. Wilson et al.'s research showed that maximal strength training improved cycling economy and time-trial performance without significantly increasing thigh cross-sectional area.

Regarding volume, accumulating 6–10 sets per major exercise per week, training 2–3 times per week, is considered by most meta-analyses to be the sweet spot balancing benefits and recovery. The table below presents a typical dose-response relationship:

Dose Range	Recommended Configuration	Applicable Period	Expected Benefit	Interference/Fatigue Risk
Minimum effective dose	1×/week, 2–3 sets per exercise	Maintenance, in-season	Small	Low
Standard effective dose	2×/week, 3–4 sets per exercise	Base, development	Medium–large	Medium
High dose	3×/week, 4–6 sets per exercise	Off-season strength specialization	Large (but diminishing returns)	High (interference risk↑)

Individual differences play a major role here. Genetic polymorphisms (e.g., ACTN3, muscle fiber composition), training history, nutritional status, and recovery capacity all cause the same program to produce different results in different people. The “responder vs. low-responder” phenomenon commonly seen in research reminds us that dosage must be individualized and continuously monitored with objective indicators (e.g., 1RM progress, RFD, time-trial performance). A practical principle is: establish a foothold at the minimum effective dose, then progressively overload, and decisively step back when signs of poor recovery or stagnant endurance performance appear.

Particularly in the context of concurrent training, the “ceiling” of dosage is often determined not by strength adaptation but by the degree to which it competes with endurance training for recovery resources. This is why elite endurance athletes’ strength training doses are typically far more conservative than those of pure strength athletes—they seek “sufficient” strength stimulus, not “maximal” strength stimulus.

Differences Across Populations

The benefits of resistance training on running economy are not “one-size-fits-all”; population characteristics significantly moderate the direction and magnitude of adaptation.

Beginners vs. advanced athletes. For strength training novices, the rapid early progress comes almost entirely from neural adaptation, with benefits that are significant and easily obtained (the so-called “beginner bonus”). However, for advanced athletes with years of training foundation, the nervous system’s “ceiling” is lower, and continued progress often requires more refined periodization, higher intensity, or novel stimuli (such as eccentric overload or power-oriented approaches). Research shows that effect sizes for advanced athletes are typically smaller than for beginners, but because their performance is already near personal limits, even a 1–2% improvement can be decisive in competition.

Sex differences. Vikmoen et al.'s research on female road cyclists is particularly important because early literature focused predominantly on males. Results show that women equally benefit from strength training in terms of running economy and time-trial performance, and because women’s relative muscle mass starting point is lower, some studies even observe greater relative room for improvement. Differences in hormonal environment (testosterone) between sexes primarily affect the absolute magnitude of hypertrophy, not the “direction” of neural and tendon adaptations.

Age differences. With advancing age, the loss of fast-twitch muscle fibers and motor units (sarcopenia) turns strength training from “icing on the cake” into “indispensable.” The table below summarizes adaptation characteristics and training priorities for different populations:

Population	Adaptation Characteristics	Training Priorities
Beginners	Neural adaptation dominant, rapid progress	Establish movement quality, progressive loading
Advanced athletes	Adaptation slows, needs refined stimuli	Periodization, power/eccentric focus
Female athletes	Relatively larger room for improvement	Same principles as males, avoid over-conservatism
Older athletes (>50)	Anti-sarcopenia, neural loss	Maintain high-intensity stimulus, emphasize RFD
Adolescents	Prioritize movement technique and safety	Start with bodyweight, avoid early heavy loads

Understanding these differences allows athletes and coaches to avoid forcing a single program onto everyone and to make reasonable adjustments based on their own stage and conditions. It is worth noting that population categories are just a starting point; true individualization must return to each athlete’s response data.

Practical Training Application

Translating research into a training plan requires answering four questions: what exercises to do, what intensity to use, when to schedule them, and how to monitor.

Exercise selection. For cycling and running, the most transferable exercises are multi-joint, closed-chain movements covering the hip-knee-ankle extension chain—squats, deadlifts, single-leg squats, step-ups, and calf raises. For the specific goal of improving running economy through resistance training, supplementary exercises (such as eccentric components, plyometric jumps, or core stability training) can be added.

Intensity and sets. When maximal strength is the primary goal, 4–6RM with 3–4 sets per exercise and rest intervals of 3 minutes or more to ensure quality is recommended. If the goal leans toward power and RFD, switch to lighter loads (30–60% 1RM) with “maximal intended velocity” execution, where movement speed itself is the stimulus. Below is an example weekly schedule for the off-season:

Day	Main Training	Strength Program Example
Monday	Endurance (long aerobic)	—
Tuesday	Strength (maximal strength focus)	Squat 5×5, Romanian deadlift 4×6, calf raise 3×8
Wednesday	Endurance (tempo/threshold)	—
Thursday	Strength (power focus)	Jump squat 5×3, single-leg step-up 3×6, core circuit
Friday	Recovery/technique	—
Saturday	Long endurance or race simulation	—
Sunday	Complete rest	—

Timing. To reduce interference effects, if both types of training are done on the same day, it is recommended to separate strength and high-intensity endurance sessions by at least 6 hours, or place them on different days; when they must be on the same day, prioritize the ability you want to develop first (early in the season, strength often comes first; mid-season, endurance often comes first).

Monitoring indicators. Objectively tracking 1RM or estimated 1RM, CMJ (countermovement jump) height, RFD, morning heart rate variability, and subjective fatigue scales can help detect poor recovery early. When CMJ declines consecutively or time-trial performance stagnates, treat it as a signal to adjust dosage. Remember: strength training is the “auxiliary engine” for endurance performance; its purpose is to make you more efficient on the racecourse, not to lift heavier in the gym. Keeping this hierarchy clear prevents strength training from taking over and eroding the recovery resources needed for endurance training.

Local Application in Taiwan

Taiwan’s climate, terrain, and racing culture bring several unique considerations to the application of resistance training for improving running economy.

Recovery management in hot, humid weather. Taiwan’s summer heat and humidity can hinder recovery after strength training due to dehydration and impaired sleep quality. It is recommended to schedule heavy lifting in the early morning or in an air-conditioned indoor gym, and to pay special attention to post-training hydration, electrolyte, and protein intake, avoiding stacking high-intensity endurance and strength stimuli on hot afternoons to prevent exacerbating interference effects.

Specific demands of climbing races. Classic Taiwanese events such as Wuling (west approach), North-to-Wuling, and the Yangmingshan series (Fengguizui, Balaka) are known for long distances with massive elevation gain. These events place extremely high demands on “sustained output at low cadence and high torque,” a scenario where maximal strength and single-leg strength training can transfer directly. For challenges like Wuling with its 3,000-meter elevation changes, lower-body maximal strength reserves allow riders to maintain pedaling capacity on the later steep sections, avoiding the dreaded “legs giving out first.”

Local training resources and seasonal rhythm. Gyms are widely available in most Taiwanese counties and cities, allowing cyclists to use the free weights area for squats and deadlifts; those training at home can achieve similar stimuli with kettlebells, resistance bands, and bodyweight single-leg exercises. For cyclists whose main training grounds are Yangmingshan, Beiyi, and the Central Cross-Island Highway, it is recommended to concentrate a strength specialization block during the off-season (typically the hottest summer period, unsuitable for long outdoor sessions), turning the hot season into a golden window for building a strength foundation, then returning outdoors in the cooler autumn and winter to convert that strength into actual riding performance. In this way, Taiwan’s unique seasonal rhythm can perfectly align with strength training periodization, becoming a strategic advantage for local athletes.

Common Myth-Busting

Many claims circulating about resistance training and running economy contradict academic evidence; here they are clarified one by one.

Myth 1: “Lifting weights will make you bulky and heavy, dragging down endurance.” Evidence shows that maximal-strength-oriented training (high intensity, low volume) primarily produces neural and tendon adaptations, with limited increases in muscle cross-sectional area; most studies show no significant change in body weight, while performance improves due to enhanced efficiency.

Myth 2: “Endurance athletes should only do high-repetition, light-weight ‘muscular endurance’ training.” The opposite is true: high-repetition, light-weight training provides insufficient stimulus for neural drive and tendon stiffness, and many studies indicate that heavy-load, low-repetition training has better transfer benefits.

Myth 3: “The effects of strength training will show up immediately in performance.” Although neural adaptations are fast, tendon remodeling and muscle fiber conversion take weeks to months; giving up too early is a common mistake.

Myth 4: “The interference effect of concurrent training will cancel out the benefits of strength training.” The interference effect does exist, but its magnitude depends heavily on training order, spacing, and dosage; with proper arrangement, strength and endurance can absolutely coexist and thrive. Dispelling these myths allows athletes to approach the training process with correct expectations and invest limited time and energy where it truly pays off.

Conclusion

Looking at the evidence reviewed in this article, the improvement of running economy through resistance training is no longer a question of “whether to do it,” but “how to do it smarter.” From immediate neuromuscular adaptations, to long-term remodeling of muscle fibers and tendons, to overall improvements in running economy, multi-layered mechanisms jointly support one conclusion: appropriate resistance training is an indispensable component of the endurance athlete’s toolkit.

Future research directions include predicting individual responses using genetic and molecular markers, clarifying the optimal molecular-level spacing for concurrent training, and developing new resistance training equipment with greater sport specificity. For Taiwanese cyclists and runners, the most practical course of action is: build a solid maximal strength foundation in the off-season, maintain it with the minimum effective dose during the season, and monitor throughout with objective indicators, allowing strength to truly translate into speed and endurance on the racecourse. Science has provided the direction; the rest is putting it into practice with every squat down and stand up.

Related Reading

• Tendon Stiffness Training and Energy Storage: The Resistance Training Basis of the Running Spring Model
• The Impact of Strength Training on Ground Reaction Forces in Running: Biomechanical Adaptation Research
• Neural Drive Improvements from Strength Training: A Temporal Analysis of EMG Studies
• Why Endurance Athletes Need Strength Training: The Dual Key of Economy and Injury Prevention