Abstract

Purpose: The purpose of the study was to jointly estimate the effects of body mass and age on the total of the sum of snatch and clean & jerk in weightlifting and to examine sex- and age-related performance decline in male and female Masters weightlifters. Methods: Generalized additive models for location, scale, and shape were used to estimate the distribution of the weightlifting total, based on world championships of Masters athletes 2018–2025 and checked for robustness during 2000–2025. The model ranks weightlifting performances on the same scale for both sexes across body mass and age. Results: Among 4939 Masters weightlifting results (ages 35–92), a higher total correlated with a higher body mass, but this effect weakened with age (P < .001). Body mass (mean = 85.6 kg for males, 67.7 kg for females) had a 1.5 times larger impact on the total in males. The decline with age was steeper for females between ages 45 and 55 but otherwise similar to males. Scaled performances over 25 years (12,060 results) were stable over time in males but rose to a plateau from 2018 in females. Conclusions: Weightlifting performances based on the total can be ranked on the same scale for male and female Masters athletes. This method can be incorporated in competitions for mixed teams. It aids athletes, coaches, and health professionals in monitoring progress over time relative to the performance of age and body mass groups.

Abstract

Background

Older adults may have reduced amino acid (AA) digestibility due to physiological changes in the digestive tract, but quantification of reduced AA digestibility in humans is lacking.

Objective

This randomized crossover study investigated differences in indispensable AA digestibility, primarily focusing on threonine and lysine, between young and older adults for milk, sorghum, and black beans using the dual tracer method.

Methods

Ten young (21.8±1.7 years) and ten older (72.8±3.8 years) adults ingested 20 grams ^(2)H-labelled protein from either milk, sorghum or black beans, mixed with 400 mg of a ^(13)C-labelled AA mixture, in a plateau feeding protocol on three separate test days. Blood was sampled before and at regular intervals over an eight-hour period following meal consumption. The ^(2)H- and ^(13)C- enrichments of AAs in plasma samples were determined at steady state (5.5-8.0 hours). The ratio of the ^(2)H/^(13)C-ratio between blood plasma and test meals was calculated. For lysine and threonine, this ratio was compared statistically between age groups and protein sources using linear mixed model analysis.

Results

The isotope plasma-to-meal ratio for lysine and threonine was 19% lower in older adults compared to young adults for sorghum (P=0.041), whereas it was not significantly different for milk (P=0.277) and black beans (P=0.849).

Conclusions

Lysine and threonine digestion might be lower in older versus young adults but the effect differed among protein sources. Further research on how ageing affects protein digestibility across protein sources is needed to optimize dietary protein recommendations for older adults.