Telomeres, exercise and cardiovascular disease : Finding the means to justify the ends
- Authors: Chilton, Warrick , O'Brien, Brendan , Grace, Fergal , Charchar, Fadi
- Date: 2017
- Type: Text , Journal article
- Relation: Acta Physiologica Vol. 220, no. 2 (2017), p. 186-188
- Full Text: false
- Reviewed:
Aortic augmentation index in endurance athletes : A role for cardiorespiratory fitness
- Authors: Denham, Joshua , Brown, Nicholas , Tomaszewski, Maciej , Williams, Bryan , O’Brien, Brendan , Charchar, Fadi
- Date: 2016
- Type: Text , Journal article
- Relation: European Journal of Applied Physiology Vol. 116, no. 8 (2016), p. 1537-1544
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
- Full Text: false
- Reviewed:
- Description: Purpose: Endurance exercise improves cardiovascular health and reduces mortality risk. Augmentation index (AIx) reflects adverse loading exerted on the heart and large arteries and predicts future cardiovascular disease. The purpose of this study was to establish whether endurance athletes possess lower AIx and aortic blood pressure compared to healthy controls, and to determine the association between AIx and cardiorespiratory fitness. Methods: Forty-six endurance athletes and 43 healthy controls underwent central BP and AIx measurements by non-invasive applanation tonometry before a maximal exercise test. Peak oxygen uptake (V˙ O 2 peak) was assessed by pulmonary analysis. Results: Relative to controls, athletes had significantly lower brachial diastolic blood pressure (BP, −4.8 mmHg, p < 0.01), central systolic BP (−3.5 mmHg, p = 0.07), and AIx at a heart rate of 75 beats min−1 (AIx@75, −11.9 %, p < 0.001). No AIx@75 differences were observed between athletes and controls when adjusted for age and V˙ O 2 peak [athletes vs controls mean (%) ± SE: −6.9 ± 2.2 vs −5.7 ± 2.3, p = 0.76]. Relative to men with low V˙ O 2 peak, those with moderate and high V˙ O 2 peak had lower age-adjusted AIx@75 (p < 0.001). In women, those with high V˙ O 2 peak had lower AIx@75 than those with low and moderate V˙ O 2 peak (p < 0.01). Conclusions: The lower AIx@75 in endurance athletes is partly mediated by V˙ O 2 peak. While an inverse relationship between AIx@75 and V˙ O 2 peak was found in men, women with the highest V˙ O 2 peak possessed lowest AIx@75 compared to females with moderate or poor cardiorespiratory fitness. We recommend aerobic training aimed at achieving a minimum V˙ O 2 peak of 45 ml kg−1 min−1 to decrease the risk of future cardiovascular events and all-cause mortality.
- Description: Purpose: Endurance exercise improves cardiovascular health and reduces mortality risk. Augmentation index (AIx) reflects adverse loading exerted on the heart and large arteries and predicts future cardiovascular disease. The purpose of this study was to establish whether endurance athletes possess lower AIx and aortic blood pressure compared to healthy controls, and to determine the association between AIx and cardiorespiratory fitness. Methods: Forty-six endurance athletes and 43 healthy controls underwent central BP and AIx measurements by non-invasive applanation tonometry before a maximal exercise test. Peak oxygen uptake (V˙ O 2 peak) was assessed by pulmonary analysis. Results: Relative to controls, athletes had significantly lower brachial diastolic blood pressure (BP, −4.8 mmHg, p < 0.01), central systolic BP (−3.5 mmHg, p = 0.07), and AIx at a heart rate of 75 beats min−1 (AIx@75, −11.9 %, p < 0.001). No AIx@75 differences were observed between athletes and controls when adjusted for age and V˙ O 2 peak [athletes vs controls mean (%) ± SE: −6.9 ± 2.2 vs −5.7 ± 2.3, p = 0.76]. Relative to men with low V˙ O 2 peak, those with moderate and high V˙ O 2 peak had lower age-adjusted AIx@75 (p < 0.001). In women, those with high V˙ O 2 peak had lower AIx@75 than those with low and moderate V˙ O 2 peak (p < 0.01). Conclusions: The lower AIx@75 in endurance athletes is partly mediated by V˙ O 2 peak. While an inverse relationship between AIx@75 and V˙ O 2 peak was found in men, women with the highest V˙ O 2 peak possessed lowest AIx@75 compared to females with moderate or poor cardiorespiratory fitness. We recommend aerobic training aimed at achieving a minimum V˙ O 2 peak of 45 ml kg−1 min−1 to decrease the risk of future cardiovascular events and all-cause mortality. © 2016, Springer-Verlag Berlin Heidelberg.
Epigenetic changes in leukocytes after 8 weeks of resistance exercise training
- Authors: Denham, Joshua , Marques, Francine , Bruns, Emma , O'Brien, Brendan , Charchar, Fadi
- Date: 2016
- Type: Text , Journal article
- Relation: European Journal of Applied Physiology Vol. 116, no. 6 (2016), p. 1245-1253
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
- Full Text: false
- Reviewed:
- Description: PURPOSE: Regular engagement in resistance exercise training elicits many health benefits including improvement to muscular strength, hypertrophy and insulin sensitivity, though the underpinning molecular mechanisms are poorly understood. The purpose of this study was to determine the influence 8 weeks of resistance exercise training has on leukocyte genome-wide DNA methylation and gene expression in healthy young men. METHODS: Eight young (21.1 +/- 2.2 years) men completed one repetition maximum (1RM) testing before completing 8 weeks of supervised, thrice-weekly resistance exercise training comprising three sets of 8-12 repetitions with a load equivalent to 80 % of 1RM. Blood samples were collected at rest before and after the 8-week training intervention. Genome-wide DNA methylation and gene expression were assessed on isolated leukocyte DNA and RNA using the 450K BeadChip and HumanHT-12 v4 Expression BeadChip (Illumina), respectively. RESULTS: Resistance exercise training significantly improved upper and lower body strength concurrently with diverse genome-wide DNA methylation and gene expression changes (p = 0. 01). DNA methylation changes occurred at multiple regions throughout the genome in context with genes and CpG islands, and in genes relating to axon guidance, diabetes and immune pathways. There were multiple genes with increased expression that were enriched for RNA processing and developmental proteins. Growth factor genes-GHRH and FGF1-showed differential methylation and mRNA expression changes after resistance training. CONCLUSIONS: Our findings indicate that resistance exercise training improves muscular strength and is associated with reprogramming of the leukocyte DNA methylome and transcriptome.