Key result
12-week vigorous cycling increases VO2max by ~20%, driven by cardiac, vascular, and mitochondrial adaptations.
Why the study?
This study aimed to examine the central and peripheral physiological adaptations contributing to increases in maximal oxygen uptake following a 12-wk vigorous endurance exercise program in healthy older and young adults.
Does a 12-week vigorous endurance cycling program improve VO2max and physiological adaptations in healthy older and young adults?
Does a 12-week vigorous endurance cycling program improve VO2max and physiological adaptations in healthy older and young adults?
p-value: p=< 0.05
A 12-week endurance training program improves cardiorespiratory fitness in both young and older adults primarily through enhanced central cardiac function and peripheral vascularization and mitochondrial activity.
May support fitness gains via cardiac and mitochondrial adaptations in healthy adults; leaves open generalizability and age effects pending larger trials.
PURPOSE: This study aimed to examine central and peripheral physiological adaptations contributing to increases in maximal oxygen uptake (V̇O 2max ) following a 12-wk vigorous endurance exercise program in healthy, older and young adults. METHODS: Fourteen participants (7 older: 68 ± 7 yr and 7 young: 26 ± 7 yr; 9 males and 5 females) engaged in a cycling training program three times a week for 45 min at ~70%V̇O 2max . Changes in V̇O 2max , cardiac function, V̇O 2 extraction, muscle capillarization, and mitochondrial content from pre- to post-training were examined. RESULTS: The increase in V̇O 2max from pre- to post-training for all participants (20% ± 8%) was accompanied by increases in maximal cardiac output (Q˙ max ; 15% ± 11%), maximal stroke volume (SVmax; 14% ± 12%), muscle fiber cross-sectional area (CSA; 17% ± 21%) and perimeter (P; 7% ± 9%), citrate synthase (CS) activity (144% ± 175%), individual capillary-to-fiber ratio (C:Fi; 32% ± 17%), capillary-to-fiber perimeter exchange index (CPFE: 30% ± 15%), capillary contact (CC; 38% ± 20%), capillary density (CD; 22% ± 17%), and arteriovenous O 2 difference (a-vO 2 diff; 4% ± 6%) ( P < 0.05 for all). No training-related variation existed for maximal heart rate (HRmax; -1% ± 4%; P = 0.448). Changes in V̇O 2max were positively correlated with Q˙ max ( r = 0.830: P < 0.001), SVmax ( r = 0.655; P = 0.011), CD ( r = 0.546; P = 0.043), and CS activity ( r = 0.630; P = 0.021). No significant correlations were found for changes in V̇O 2max and changes in HRmax, a-vO 2 diff, muscle fiber CSA and P, CC, C:Fi, and CPFE ( P > 0.05 for all). CONCLUSIONS: Cardiorespiratory fitness improvements were primarily determined by enhancement in central (i.e., cardiac function) and peripheral (i.e., vascularization) adaptations within the V̇O 2 transport system as well as the upregulation of mitochondrial aerobic enzymatic activity (i.e., CS activity) at the intracellular level.
No takes yet. Share an insight, caveat, or question.
Faricier et al. (2025) studied Healthy adults (n=14). Vigorous endurance exercise program (cycling) was evaluated on Changes in VO2max from pre- to post-training (p=< 0.05). A 12-week vigorous endurance cycling program increased VO2max by 20% ± 8% (P<0.05), driven by central cardiac and peripheral vascular adaptations and upregulated mitochondrial enzyme activity.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: