# The Effect of Tongkat Ali Supplementation on Body Composition in Exercise-Trained Males and Females
## 1 Introduction  
Eurycoma longifolia Jack, commonly known as \"Tongkat Ali\", is an herbal medicinal plant from Southeast Asia [1]. Traditionally, various parts of the plant have been purportedly utilized for their therapeutic properties, including antimalarial, aphrodisiac, anti-diabetic, antimicrobial, and anti-pyretic effects despite the dearth of scientific evidence [1]. Tongkat Ali has been purported to assist with erectile dysfunction [2], increase testosterone concentration [3], and improve mood [4]. To assess the effects of Tongkat Ali in aging males, scientists conducted a 6-month randomized, double-blind, placebo-controlled clinical trial involving 45 men (mean age: 47.38 \(\pm\) 5.03 years) [5]. Both exercise training and Tongkat Ali supplementation showed improvements in erectile function, with the mostsignificant enhancements observed in men undergoing concurrent training combined with Eurycoma longifolia supplementation [5]. In one of the few investigations that involved exercise training, [PERSON] et al. examined the combined effects of a resistance training program and Eurycoma longifolia Jack on isokinetic muscular strength and power, anaerobic power, and urinary testosterone-to-epitestosterone (T/E) ratio in young males [6]. These investigators took 40 young males who were weight-matched and randomized to one of four groups: control (C), Eurycoma longifolia Jack (ELJ), resistance training (RT), and Eurycoma longifolia Jack plus resistance training (ELJ and RT). Participants in the ELJ and EIJ and RT groups consumed 200 mg of Eurycoma longifolia Jack daily, while those in the C and RT groups took placebo capsules daily for eight weeks. The resistance training program, consisting of 10 different exercises, was conducted thrice weekly for eight weeks. The resistance training program included ten stations featuring various exercises using elastic bands or dumbbells [6]. The exercises were heel raises with dumbbells, lateral raises with elastic bands, leg curls with elastic bands, bicep curls with dumbbells, leg abductions with elastic bands, front raises with dumbbells, knee extensions with elastic bands, arm extensions with dumbbells, half squats with elastic bands, and standing chest flies with dumbbells. Each exercise with dumbbells involved 10 repetitions, while those with elastic bands involved 15 repetitions. The dumbbells weighed between three and 12 kg, and the elastic bands were color-coded according to their elasticity. Participants rested for 1 min between stations and had a 3 min rest before starting a new set. They completed three sets of this circuit, and the program was conducted three times a week for eight weeks. It should be noted that these individuals were initially untrained. Isokinetic muscular strength and power, anaerobic power, and urinary T/E ratio were measured before and after the intervention [6]. After eight weeks of intervention, significant increases in the isokinetic average power of knee flexion at 300\({}^{\circ}\)/s were observed in the resistance training and combined ELJ and RT groups. In contrast, the control and ELJ-supplemented groups showed no changes in isokinetic muscular strength and average power from pre- to post-intervention. These findings indicate that resistance training enhanced lower limb power in participants. On the other hand, ELJ alone does not affect the training response. Moreover, there have been no studies that have examined an exercise-trained population. More importantly, body composition has not been assessed. Indeed, if free testosterone (i.e., the biologically active form) is chronically elevated after the consumption of Tongkat Ali, one would expect a change in body composition. Thus, the purpose of this investigation was to determine if one month of Tongkat Ali supplementation affected indices of body composition, mood, sleep, physical performance, and salivary cortisol and testosterone concentration in exercise-trained males and females.