Individual physiological and mitochondrial responses during 12 weeks of intensified exercise.
Physiol Rep
; 9(15): e14962, 2021 08.
Article
en En
| MEDLINE
| ID: mdl-34327858
ABSTRACT
AIM:
Observed effects of exercise are highly variable between individuals, and subject-by-training interaction (i.e., individual response variability) is often not estimated. Here, we measured mitochondrial (citrate synthetase, cytochrome-c oxidase, succinate dehydrogenase, and mitochondrial copy-number), performance markers (Wpeak , lactate threshold [LT], and VO2peak ), and fiber type proportions/expression (type I, type IIa, and type IIx) in multiple time points during 12-week of high-intensity interval training (HIIT) to investigate effects of exercise at the individual level.METHODS:
Sixteen young (age 33.1 ± 9.0 years), healthy men (VO2peak 35-60 ml/min/kg and BMI 26.4 ± 4.2) from the Gene SMART study completed 12-week of progressive HIIT. Performance markers and muscle biopsies were collected every 4 weeks. We used mixed-models and bivariate growth models to quantify individual response and to estimate correlations between variables.RESULTS:
All performance markers exhibited significant (Wpeak 0.56 ± 0.33 p = 0.003, LT 0.37 ± 0.35 p = 0.007, VO2peak 3.81 ± 6.13 p = 0.02) increases overtime, with subject-by-training interaction being present (95% CI Wpeak 0.09-0.24, LT 0.06-0.18, VO2peak 0.27-2.32). All other measurements did not exhibit significant changes. Fiber type IIa proportions at baseline was significantly associated with all physiological variables (p < 0.05), and citrate synthetase and cytochrome-c oxidase levels at baseline and overtime (i.e., intercept and slope) presented significant covariance (p < 0.05). Finally, low correlations between performance and mitochondrial markers were observed.CONCLUSION:
We identified a significant subject-by-training interaction for the performance markers. While for all other measures within-subject variability was too large and interindividual differences in training efficacy could not be verified. Changes in measurements in response to exercise were not correlated, and such disconnection should be further investigated by future studies.Palabras clave
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Consumo de Oxígeno
/
Adaptación Fisiológica
/
Biomarcadores
/
Ejercicio Físico
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Entrenamiento de Intervalos de Alta Intensidad
/
Capacidad Cardiovascular
/
Mitocondrias
Tipo de estudio:
Prognostic_studies
Límite:
Adolescent
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Adult
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Physiol Rep
Año:
2021
Tipo del documento:
Article
País de afiliación:
Australia