Dietary Supplementation

This is a randomized, double-blind, placebo-controlled clinical trial exploring the effects of a 12-week dietary supplement regimen on skin condition and perceived overall health status. The study will involve 120 healthy Chinese adults aged 18 and above with low daily fruit and vegetable intake. Participants will be randomly assigned to one of two groups: one group will take a combination of Nu Skin's Vitamin C \& Green Tea Capsules and Multivitamin \& Mineral Capsules, while the other group will take a matching placebo. The primary goal is to assess if the supplement combination improves skin health after 12 weeks, measured through specialized facial imaging (assessing spots, redness, evenness) and probe measurements (assessing elasticity, moisture, gloss). Secondary goals include evaluating changes in participants' self-perceived health status (via quality of life, fatigue, and digestive health questionnaires), psychological resilience, memory, and exploring a new method for measuring skin carotenoid levels. This study is not intended to verify the approved health functions of the products but to explore the potential combined effects of antioxidant and nutritional supplementation on skin and general well-being.

Resistance exercise training (RET) in children and adolescents has become a popular area of research, with a growing body of evidence supporting its use. Position and consensus statements about RET for children indicate that it is safe and effective at increasing muscular strength, improving sport performance, and mitigating injury risk. Neural and muscular mechanisms can improve muscle strength following RET. Neural factors include improved recruitment and firing of an individual's motor units, and muscular factors primarily include an increase in the size of the muscle (hypertrophy). In children, little is known about how these mechanisms relate to muscle strength. There is very little evidence of morphological changes following RET in children. Therefore, conventional wisdom is that children rely only on neural factors to improve strength following RET. Nevertheless, some studies have suggested RET-induced muscle hypertrophy in children and adolescents, indicating that with certain training protocols, children may achieve muscle growth. Hypertrophy of muscle fibres occurs when the rate of muscle protein synthesis (MPS) is greater than the rate of protein breakdown, and is enhanced with the ingestion of dietary amino acids. Due to ethical concerns with obtaining muscle samples (i.e., from muscle biopsies) in pediatric populations, MPS rates have not been previously assessed following RET in children. Recent advancements in stable-isotope methodology (specifically, leucine) allow for the estimation of MPS in a non-invasive breath test. The objective of the proposed research is to examine the effects of an acute bout of RET on leucine retention (a proxy for MPS) in children, adolescents, and adults using a non-invasive breath test.