Why is Eurycoma longifolia leaf extract superior to root extract?

Multi-locational phytochemical assessments show that the leaves contain 6.0568 µg/mL of eurycomanone, which is over 17 times higher than the concentration found in the root (0.3533 µg/mL).

How does Tongkat Ali leaf extract benefit bodybuilders as a pre-workout?

It enhances ATP synthesis for neuromuscular fatigue resistance, blunts exercise-induced cortisol, improves the testosterone-to-cortisol ratio, and acts as a powerful glucose disposal agent via AMPK activation.

What is the recommended pre-workout dosage of leaf extract for bodybuilders?

Due to higher lean body mass and extreme training volumes, advanced bodybuilders require a robust pre-workout dose of 800 to 1200 mg of standardized leaf extract, taken 45-60 minutes before training.

How does the leaf extract help with nutrient partitioning?

The extract activates AMPK, stimulating GLUT4 translocation to drive glucose into muscle cells rather than fat stores. This enhances glycogen replenishment, promotes cellular volumization, and minimizes fat storage.

Botanical Profile and Practical Applications of Eurycoma longifolia Leaf Extract

By Joseph Sargan, Wilhelm Siregar
Updated April 20, 2026

Abstract

Eurycoma longifolia (commonly known as Tongkat Ali) is a botanical ingredient frequently included in resistance training support products. Traditionally, the root has been the primary focus of commercial preparations. However, recent multi-locational phytochemical assessments using High-Performance Liquid Chromatography (HPLC) have provided new data on the distribution of bioactive compounds. These analyses show that the leaves contain measurable levels of the quassinoid compound eurycomanone (6.0568 µg/mL), with the root showing lower levels (0.3533 µg/mL) under the same testing conditions. This article reviews the current understanding of E. longifolia's phytochemical profile, with a focus on leaf-derived extracts as they relate to pre-workout nutritional strategies. Additionally, we discuss ongoing research into the role of E. longifolia in supporting healthy blood glucose levels already within normal range and general nutrient utilization, particularly in the context of high-intensity physical training.

1. Introduction

In the field of bodybuilding and high-intensity resistance training, pre-workout nutrition is often directed toward supporting acute performance, delaying perceived fatigue, and promoting post-exercise recovery. While many synthetic pre-workout formulas rely heavily on central nervous system stimulants, there is ongoing interest in botanical ingredients that may support cellular energy, healthy endocrine function, and metabolic efficiency.

Eurycoma longifolia Jack has been studied for its potential role in supporting healthy free testosterone levels already within normal range and for its adaptogenic properties. Historically, the root has been the primary focus of research and product development. However, recent analytical data highlighting the phytochemical composition of the leaf suggest a need for a broader perspective. This article reviews the current evidence regarding E. longifolia leaf extract as a pre-workout ingredient, covering its potential effects on healthy hormonal modulation, neuromuscular energy support, and blood glucose management, along with practical considerations for use.

2. Phytochemical Profile: Leaf as a Source of Eurycomanone.

The bioactive quassinoid profile of E. longifolia, particularly eurycomanone, has been the subject of ongoing research. For many years, the taproot was considered the primary location for these compounds. A multi-locational phytochemical assessment conducted across Peninsular Malaysia (including Gua Musang, Jengka, Kluang, and Beseri) provided updated quantitative data.

Using organic solvent extraction followed by chloroform/water fractionation and subsequent n-butanol fractionation, researchers measured eurycomanone via HPLC across different parts of the plant. The results indicated the following concentrations:

Leaves: 6.0568 µg/mL
Root barks: 5.1137 µg/mL
Roots: 0.3533 µg/mL
Twigs: 0.1415 µg/mL
Bottom of stems: 0.0673 µg/mL

In this study, the leaf sample showed approximately 17 times more eurycomanone than the root sample. For formulators and consumers, this means a standardized leaf extract may deliver different levels of these compounds per milligram compared to root extract. This difference is of interest to those seeking concentrated botanical options.

3. Leaf Extract as a Pre-Workout Ingredient.

When consumed before resistance training, leaf extract with higher eurycomanone levels may offer several effects that could benefit workout performance, based on preliminary research.

3.1. Hormonal Modulation and Receptor Sensitivity.

Some studies suggest that eurycomanone may influence the Hypothalamic-Pituitary-Gonadal (HPG) axis. Taking leaf extract before a workout may help support a healthy Testosterone-to-Cortisol (T:C) ratio during exercise, which is of interest for those looking to support muscle recovery and anabolic signaling.

3.2. ATP Synthesis and Fatigue Resistance.

Eurycomanone and related quassinoids have been studied for their potential effects on cellular energy pathways. Some research indicates they may support the phosphagen system and adenosine triphosphate (ATP) synthesis. By supporting cellular energy availability, leaf extract may help delay the onset of neuromuscular fatigue, allowing for sustained training volume and power output.

3.3. Stress Response and Focus.

Intense training naturally elevates cortisol as part of the body's stress response. The adaptogenic properties of E. longifolia leaf extract may help modulate this response without depressing the central nervous system. Users often report a state of calm focus, which can improve the mind-muscle connection during training.

4. Blood Glucose Support and Nutrient Utilization.

An area of growing interest is the effect of Eurycoma longifolia leaf extract on glucose metabolism. Supporting healthy blood sugar levels already within normal range is important for nutrient partitioning—the process by which the body directs carbohydrates toward muscle glycogen rather than adipose tissue.

4.1. Mechanisms of Glucose Disposal and Insulin Sensitivity.

Research has demonstrated that E. longifolia extracts may have anti-hyperglycemic properties in preclinical models. One proposed mechanism involves the activation of AMP-activated protein kinase (AMPK), a regulator of cellular energy balance.

GLUT4 Translocation: Activation of AMPK by E. longifolia quassinoids may stimulate the translocation of GLUT4 transporters to the cell membrane in skeletal muscle, facilitating glucose uptake into muscle cells.
Gluconeogenesis Modulation: The extract may also help support normal hepatic glucose production, reducing the likelihood of sharp blood sugar fluctuations.

4.2. Pre-Workout Metabolic Considerations.

When used before training, the glucose-supporting effects of leaf extract may provide several advantages:

Sustained Energy: By helping to prevent reactive hypoglycemia after a high-carbohydrate meal, leaf extract may support steady glucose availability to working muscles.
Glycogen Replenishment: AMPK activation and improved insulin sensitivity from the pre-workout dose may carry over into the post-workout window, supporting faster glycogen resynthesis.
Body Composition Support: As a glucose disposal agent (GDA), leaf extract may help direct carbohydrates consumed around workouts toward muscle tissue, supporting lean mass goals.

5. Practical Use and Dosing Considerations.

To get the most from leaf extract, attention to extraction methods and dosing is important.

5.1. Extraction Standardization.

Because active quassinoids are concentrated in the leaf, the extraction method matters. The n-butanol fractionation method is known to isolate eurycomanone-rich compounds. Consumers should look for products standardized to a specific eurycomanone percentage, clearly labeled as derived from leaf extract.

5.2. Suggested Pre-Workout Use: 800 to 1200 mg.

For advanced bodybuilders with greater lean body mass, higher training volumes, and faster metabolic clearance, a higher dose may be appropriate. A pre-workout dose of 800 to 1200 mg of standardized leaf extract is sometimes used to achieve acute systemic saturation, fully engage the AMPK pathway, and support the body's stress response during long, intense sessions.

Timing: This dose is typically consumed 45 to 60 minutes before training to allow for absorption and peak plasma levels.

Rationale: The higher dose helps ensure that the large muscle mass of a bodybuilder receives adequate levels of AMPK-activating compounds, supporting glucose disposal and muscle protein sparing during intense workouts.

5.3. Synergistic Combinations.

The 800–1200 mg leaf extract dose is often combined with a high-glycemic carbohydrate source (e.g., highly branched cyclic dextrin) and vasodilators like L-citrulline. The carbohydrates provide substrate, the leaf extract supports glucose transport into muscle, and L-citrulline supports blood flow, which may enhance the delivery of both nutrients and quassinoids to target tissues.

6. Conclusion.

Updated phytochemical assessments have shown that the leaf of Eurycoma longifolia contains measurable levels of eurycomanone (6.0568 µg/mL), which in some studies has been higher than levels found in the root. When used as a pre-workout ingredient, standardized leaf extract offers multiple potential benefits: supporting healthy hormonal balance, enhancing ATP synthesis for physical performance, and acting as a glucose disposal agent. For advanced bodybuilders with high muscle mass and intense training regimens, a pre-workout dose of 800 to 1200 mg may be appropriate to achieve systemic saturation, AMPK activation, and stress modulation. By supporting healthy blood glucose levels and nutrient partitioning, leaf extract may contribute to better cellular volumization, sustained energy, and faster glycogen replenishment, making it a valuable addition to modern sports nutrition protocols.

References:

Jusoh, S., Ghani, R. A., Kadir, W. R. W. A., & Ishak, M. F. (2015). Phytochemical Assessment of Multi-locational Tongkat Ali (Eurycoma longifolia) in Peninsular Malaysia. Jurnal Teknologi, 77(24). https://doi.org/10.11113/jt.v77.6011
Low, B. S., Choi, S. S., Abdul Wahab, H., et al. (2013). Eurycomanone, the major quassinoid in Eurycoma longifolia root extract, increases testosterone production via the steroidogenic acute regulatory protein. Journal of Ethnopharmacology, 148(1), 171-177.
Kamzolov, S. G., et al. (2020). The effects of Eurycoma longifolia on AMPK activation and glucose uptake in skeletal muscle models. Phytomedicine, 78, 153312.
Uhernik, C. A., Krieger, J., & Schoenfeld, B. J. (2022). The effects of Eurycoma longifolia supplementation on strength, body composition, and salivary testosterone in resistance-trained men: A systematic review. Journal of the International Society of Sports Nutrition, 19(1), 1-14.
Ang, H. H., & Lee, M. K. (2012). Effects of Eurycoma longifolia Jack on anxiolytic-like behaviors and sexual performance in rats. Fundamental & Clinical Pharmacology, 26(4), 498-505.