1. Does Chronic Exercise Attenuate Age-Related Physiological Decline in Males?   Lawrence D Hayes1,2, Fergal M Grace1, Nick Sculthorpe1,3, Peter Herbert4, Liam P Kilduff5, and Julien S Baker1 1Institute of Clinical Exercise and Health Science, University of the West of Scotland 2School of Human Sciences, London Metropolitan University 3Department of Sport and Exercise Sciences, University of Bedfordshire 4School of Sport, Health and Outdoor Education, Trinity Saint David, University of Wales 5Department of Sports Science, Swansea University
INTRODUCTION
Alteration in body composition, physical function, and substrate metabolism occur with advancing age. Coincident with deteriorations in clinical status, endogenous production of anabolic hormones declines (Harman et al., 2001) with age. Testosterone plays a key role in regulating muscle mass and fat free mass (Hayes et al., 2010), and it declines with age in both men (Feldman et al., 2002) and women (Davison et al., 2005).
A growing subset of older individuals has maintained higher functional capacity and quality of life through exercise. As exercise is known to increase levels of testosterone acutely (Caruso et al., 2012) and chronically (Ari et al. 2004), the primary aim of the present investigation was to determine whether chronic exercise maintains salivary testosterone levels in master athletes (MA) ~60 yrs when compared to age matched sedentary (S) middle aged to older individuals.
METHODS
The MA group had a minimum of 10 years continuous training and were primarily endurance athletes. The S group did not meet the ACSM guidelines for minimum aerobic exercise in older adults (Nelson et al., 2007). Salivary testosterone and cortisol, maximum oxygen uptake (VO2max), peak power output, and body composition was calculated. T-test examined differences between groups and Pearson’s correlation tested relationships between variables. Significance was set at p < 0.05.
RESULTS
Salivary testosterone, VO2max, and peak power output were significantly higher in the MA group than the S group (p < 0.05 [table 1]), whilst blood pressure and body fat percentage were lower (p < 0.005). Cortisol, fat free mass (FFM), and total body mass were not significantly different between groups.
VO2max correlated negatively with blood pressure, body fat percentage, FFM and body mass, yet positively with testosterone (table 2).
DISCUSSION
This investigation demonstrates that chronic exercise attenuates the age related decline in testosterone and improves anthropometry.
Salivary testosterone reflects the bioavailable steroid hormone fraction found in general blood circulation, higher levels found in the MA group may have important implications for older individuals. Higher free testosterone may indicate an improved ‘‘bioactivity status’’ in the blood .
CONCLUSION
The findings from the present investigation suggest that physical activity is essential to improve the physiological and metabolic profile of older individuals.
Variable MA S N 20 28
Stature (m)
173.6 ± 5.6
174.5 ± 6.4
Age (yrs)
60.4 ± 4.7
62.5 ± 5.3
Mass (kg)
79.2 ± 12.3**
89.7 ± 16.4
VO2max (ml∙kg∙min-1)
40.0 ± 5.7**
27.6 ± 4.8
Peak power output (W)
782.6 ± 171.9**
676.3 ± 172.6
Testosterone (pmol∙L-1)
493.8 ± 180.3*
± 138.8
Cortisol (nmol∙L-1)
3.3 ± 1.8
2.8 ±1.3
FFM (kg)
62.8 ± 5.9
64.5 ± 8.2
Body fat percentage (%)
19.7 ± 6.6**
27.6 ± 5.0
Systolic blood pressure (mmHg)
127.1 ± 12.4**
137.2 ± 14.1
Diastolic blood pressure (mmHg)
80.4 ± 6.6**
84.9 ± 6.8
Table 1 Exercise performance, hormonal, and anthropometric values between groups. Values are mean ± SD; VO2max = maximal oxygen uptake, FFM = fat free mass.
*Difference is significant at the 0.05 level.
**Difference is significant at the 0.01 level
Diastolic blood pressure
Systolic blood pressure
VO2max
Peak power output
Body fat percentage
FFM
Mass
Cortisol
-.305*
-.184
.059
-.076
-.120
-.090
Testosterone
-.197
-.041
.320**
.135
-.324**
-.004
-.272*
-.325**
-.444**
.281*
-.711**
-.293**
-.445**
Table 2 Coefficient of correlation for measured physiological parameters. VO2max = maximal oxygen uptake, FFM = fat free mass.
* Correlation is significant at the 0.05 level.
** Correlation is significant at the 0.01 level.
REFERENCES
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