| dc.description.abstract | Muscle plasticity is affected by physical activity and inactivity, and resistance training has been shown to prevent and reverse negative consequences of inactivity and disuse, such as loss of muscle strength, function, and quality. Ribosomal biogenesis has been shown to be an important factor in understanding the mechanisms behind muscle growth, where total RNA (~ 80-85% rRNA) is an important proxy marker. Resistance training-induced accumulation of total RNA / rRNA has been demonstrated, it is unclear whether the amount of rDNA dose in the genome is decisive for this accumulation. 46 healthy young adults (females: 24.9 (3.8) years; men: 25.0 (4.24) years) were included, and completed 8 weeks of strength training divided into three training modalities, 0 sets (control), 3 sets, and 6 sets; with a training frequency of 3 times/week. Strength tests, ultrasound, DXA scan, blood tests, and muscle biopsy were performed to map physiological, molecular, and, phenotypic changes. A valid qPCR-based method was developed to estimate the rDNA dose in muscle and blood tissues. Total RNA increased significantly from T2 to T3, and an association was found between rDNA dose and exercise-induced accumulated total RNA at T3 (r = 0.470; p = 0.004), but no significant association was found at T2 and post-intervention. rDNA dose did not predict the observed muscle growth measured post-intervention. Contralateral resistance training showed muscular response through increased muscle strength and muscle thickness, but it was not volume-dependent (moderate versus high). In conclusion, rDNA dose appears to be associated with exercise-induced total RNA accretion. More research is needed to determine whether rDNA dose may be a determining factor for resistance training-induced responses to ribosomal biogenesis. | |
