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1.
Supplementary Energy Increases Bone Formation during Arduous Military Training.
O'Leary, TJ, Walsh, NP, Casey, A, Izard, RM, Tang, JCY, Fraser, WD, Greeves, JP
Medicine and science in sports and exercise. 2021;(2):394-403
Abstract
PURPOSE This study aimed to investigate the effect of supplementary energy on bone formation and resorption during arduous military training in energy deficit. METHODS Thirty male soldiers completed an 8-wk military combat course (mean ± SD, age = 25 ± 3 yr, height = 1.78 ± 0.05 m, body mass = 80.9 ± 7.7 kg). Participants received either the habitual diet (control group, n = 15) or an additional 5.1 MJ·d-1 to eliminate the energy deficit (supplemented group, n = 15). Circulating markers of bone formation and resorption, and reproductive, thyroid, and metabolic status, were measured at baseline and weeks 6 and 8 of training. RESULTS Bone-specific alkaline phosphatase decreased in controls (-4.4 ± 1.9 μg·L-1) and increased in the supplemented group (16.0 ± 6.6 μg·L-1), between baseline and week 8 (P < 0.001). Procollagen type 1 N-terminal propeptide increased between baseline and week 6 for both groups (5.6 ± 8.1 μg·L-1, P = 0.005). Beta carboxy-terminal cross-linking telopeptide of type 1 collagen decreased between baseline and week 8 for both groups (-0.16 ± 0.20 μg·L-1, P < 0.001). Prolactin increased from baseline to week 8 for the supplemented group (148 ± 151 IU·L-1, P = 0.041). The increase in adiponectin from baseline to week 8 was higher in controls (4.3 ± 1.8 mg·L-1, P < 0.001) than that in the supplemented group (1.4 ± 1.0 mg·L-1, P < 0.001). Insulin-like growth factor binding protein-3 was lower at week 8 than baseline for controls (-461 ± 395 ng·mL-1, P < 0.001). CONCLUSION The increase in bone-specific alkaline phosphatase, a marker of bone formation, with supplementation supports a role of energy in osteoblastic activity; the implications for skeletal adaptation and stress fracture risk are unclear. The mechanism is likely through protecting markers of metabolic, but not reproductive or thyroid, function.
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2.
Higher DHEAS Levels Associated with Long-Term Practicing of Tai Chi.
Lai, HM, Liu, MSY, Lin, TJ, Tsai, YL, Chien, EJ
The Chinese journal of physiology. 2017;(2):124-130
Abstract
Tai Chi has many benefits for middle-aged/older individuals including improvements to muscle strength and various body lipid components. DHEAS and testosterone have anti-obesity/anti-aging characteristics and also improve libido, vitality and immunity levels. Thus, the aim of the present study was to investigate the differences between middle-aged Tai Chi practitioners (n = 17) and sedentary individuals (n = 17) in terms of leg strength, blood levels of cholesterol, triglyceride, HDL, as well as DHEAS, testosterone and cortisol. Unpaired t-tests were used to identify significant differences between the two groups. There were no significant differences in body composition, leg strength, blood lipid components and testosterone. However, the Tai Chi practitioners had higher levels of DHEAS (P < 0.01) and lower levels of cortisol (P < 0.05). Thus, Tai Chi practitioners have a higher ratio of DHEAS to cortisol, which might have potential benefits in terms of improving an individual’s health-related quality of life during the aging.
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3.
Physical exercise associated with improved BMD independently of sex and vitamin D levels in young adults.
Tønnesen, R, Schwarz, P, Hovind, PH, Jensen, LT
European journal of applied physiology. 2016;(7):1297-304
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Abstract
PURPOSE Young men and women accrue the majority of their bone mass in their teens and twenties, where their bone mass peaks (PBM), yet little is known about the roles of physical exercise, vitamin D levels and bone mineral density (BMD) near PBM. METHODS To comparatively examine the effect of physical exercise and two vitamin D levels (insufficient s-25[OH]D <50 nmol/L and sufficient s-25[OH]D >80 nmol/L) on the BMD measured at the femoral neck, total hip (bilaterally) and the lumbar spine (L2-L4) in male and female participants approaching PBM. RESULTS The insufficient s-25[OH]D group, median age 21.6 (19.8-22.8) years, and BMI 24.2 ± 5.0 kg/m(2) had BMD 0.10 (0.03, 0.17) g/cm(2) (p = 0.008) lower at all DXA-scan sites compared to the sufficient s-25[OH]D group, median age 19.5 (19.0-22.3) years, and BMI of 22.6 ± 1.8 kg/m(2). Exercise was positively associated with the BMD at all DXA-scan sites (p trend = 0.0001) and with equal benefit; there was no interaction between exercise and the DXA-scan site (p = 0.09). The male participants did not have a systematically higher BMD than the female participants for all scan sites; only for hips total and femoral neck bilaterally, while it was equal at the lumbar spine. CONCLUSION The BMD in young healthy adults is associated with physical exercise, independent of sex and s-25[OH]D status. A sufficient s-25[OH]D status was systematically associated with a higher BMD for all levels of exercise. For both sexes and vitamin D levels exercise was equally positively associated with BMD.
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The effect of a 10-week Nordic walking training program on the level of GH and LH in elderly women.
Hagner-Derengowska, M, Kałużny, K, Hagner, W, Plaskiewicz, A, Bronisz, A, Borkowska, A, Budzyński, J
Climacteric : the journal of the International Menopause Society. 2015;(6):835-40
Abstract
OBJECTIVE The aim of this study was to determine the effect of a 10-week Nordic walking training program on resting growth hormone (GH) and luteinizing hormone (LH) blood concentrations and their relationships to the values of inflammatory, metabolic, and muscle injury parameters in postmenopausal women with overweight and obesity. METHODS Thirty-two postmenopausal women with overweight or obesity (body mass index 30.5 ± 4.1 kg/m(2)), aged 59.6 ± 5.9 years were included in the investigation. Concentrations of GH, LH, C-reactive protein, total cholesterol, low density (LDL) and high density lipoprotein (HDL) cholesterol, triglycerides and albumin, as well as the plasma activity of muscle enzymes such as creatine kinase and lactate dehydrogenase, were examined before and after the participants finished a 10-week Nordic walking rehabilitation program. RESULTS After a 10-week rehabilitation period in accordance with a Nordic walking program, significant increases in blood concentrations of GH (median 47.5%) and HDL cholesterol (on average by 0.1%) as well as a decrease in LH values (on average by 19%), total cholesterol, LDL cholesterol and triglycerides (all on a similar average by between 0.1 and 0.2%), creatine kinase (on average by 14%), lactate dehydrogenase (on average by 4%), C-reactive protein (on average by 24%), and body mass index (on average by 5.7%) were found. CONCLUSIONS Nordic walking for postmenopausal women with overweight and obesity led to favorable hormonal responses, as well as improvement in muscle integrity and nutritional and inflammatory states, suggesting chronic, regular exercise as an effective tool in protecting against menopause-related catabolic processes.
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Impact of training status on LPS-induced acute inflammation in humans.
Olesen, J, Biensø, RS, Meinertz, S, van Hauen, L, Rasmussen, SM, Gliemann, L, Plomgaard, P, Pilegaard, H
Journal of applied physiology (Bethesda, Md. : 1985). 2015;(7):818-29
Abstract
The aim of the present study was to examine the impact of training status on the ability to induce a lipopolysaccharide (LPS)-induced inflammatory response systemically as well as in skeletal muscle (SkM) and adipose tissue (AT) in human subjects. Seventeen young (23.8 ± 2.5 yr of age) healthy male subjects were included in the study with eight subjects assigned to a trained (T) group and nine subjects assigned to an untrained (UT) group. On the experimental day, catheters were inserted in the femoral artery and vein of one leg for blood sampling and a bolus of 0.3 ng LPS/kg body wt was injected into an antecubital vein in the forearm. Femoral arterial blood flow was measured by ultrasound Doppler, and arterial and venous blood samples were drawn before (Pre) LPS injection and 30, 60, 90, and 120 min after the LPS injection. Vastus lateralis muscle and abdominal subcutaneous AT biopsies were obtained Pre and 60 and 120 min after the LPS injection. LPS increased the systemic plasma TNFα and IL-6 level as well as the TNFα and IL-6 mRNA content in SkM and AT of both UT and T. However, whereas the LPS-induced inflammatory response in SkM was enhanced in T subjects relative to UT, the inflammatory response systemically and in AT was somewhat delayed in T subjects relative to UT. The present findings highlight that training status affects the ability to induce a LPS-induced acute inflammatory response in a tissue-specific manner.
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Influence of exercise training and eating behavior on arterial stiffness in young healthy students.
Sîrbu, E, Buzaș, R, Mihăescu, R, Suceava, I, Lighezan, D
Wiener klinische Wochenschrift. 2015;(13-14):555-60
Abstract
AIM: Increased arterial stiffness is an important risk factor for the development of cardiovascular disease. The aim of the present study was to compare arterial function and other anthropometric parameters in trained vs sedentary, healthy young students. Furthermore, the study explores the relationship between arterial stiffness and eating behavior in these students. METHODS Two groups of healthy university students were recruited for this study. The first group consisted of 10 men and 8 women (mean age: 23.27 ± 3.2 years) with an athletic predisposition. Furthermore, over the course of 6 months this group participated in 60-min training sessions designed as interval training circuits with a frequency of three to five times a week. For comparison, a group of age-matched sedentary students (5 men and 13 women; 24.27 ± 2.6 years) were recruited from the same institution. Weight, height, body mass index (BMI), as well as neck and abdominal circumferences (ABs) were recorded. Arterial tension, heart rate, arterial stiffness measurements were simultaneously determined. Lastly, all students completed a 51-item "Eating Behavior Patterns Questionnaire". RESULTS Age, weight, BMI, AB, and blood pressure were not significantly different between the two groups (p > 0.05). The moderately aerobic trained students showed a significantly lower heart rate, neck circumference, and arterial stiffness as compared with their untrained, sedentary counterparts. Additionally, pulse wave velocity (PWV) measurements were correlated to a lower weight, heart rate, blood pressure, AB, and neck circumference (p < 0.05) found in trained subjects at the end of the 6-month training period. Furthermore, the nutritional habit analysis showed that in the sedentary group, snacking, emotional eating, and cultural/lifestyle behaviors are positively correlated with PWV (p < 0.05). CONCLUSION Healthy subjects with higher PWV may benefit from consistent aerobic exercise training to improve arterial stiffness. Our eating behavior study shows that healthy eating may improve vascular function and therefore can reduce the risk of cardiovascular diseases.
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Subcellular fractionation reveals HSP72 does not associate with SERCA in human skeletal muscle following damaging eccentric and concentric exercise.
Frankenberg, NT, Lamb, GD, Vissing, K, Murphy, RM
Journal of applied physiology (Bethesda, Md. : 1985). 2014;(11):1503-11
Abstract
Through its upregulation and/or translocation, heat shock protein 72 (HSP72) is involved in protection and repair of key proteins after physiological stress. In human skeletal muscle we investigated HSP72 protein after eccentric (ECC1) and concentric (CONC) exercise and repeated eccentric exercise (ECC2; 8 wk later) and whether it translocated from its normal cytosolic location to membranes/myofibrils. HSP72 protein increased ~2-fold 24 h after ECC1, with no apparent change after CONC or ECC2. In resting (nonstressed) human skeletal muscle the total pool of HSP72 protein was present almost exclusively in the cytosolic fraction, and after each exercise protocol the distribution of HSP72 protein remained unaltered. Overall, the amount of HSP72 protein in the cytosol increased 24 h after ECC1, matching the fold increase that was measured in total HSP72 protein. To better ascertain the capabilities and limitations of HSP72, using quantitative Western blotting we determined the HSP72 protein content to be 11.4 μmol/kg wet weight in resting human vastus lateralis muscle, which is comprised of Type I (slow-twitch) and Type II (fast-twitch) fibers. HSP72 protein content was similar in individual Type I or II fiber segments. After physiological stress, HSP72 content can increase and, although the functional consequences of increased amounts of HSP72 protein are poorly understood, it has been shown to bind to and protect protein pumps like SERCA and Na(+)-K(+)-ATPase. Given no translocation of cytosolic HSP72, these findings suggest eccentric contractions, unlike other forms of stress such as heat, do not trigger tight binding of HSP72 to its primary membrane-bound target proteins, in particular SERCA.
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Regional fat changes induced by localized muscle endurance resistance training.
Ramírez-Campillo, R, Andrade, DC, Campos-Jara, C, Henríquez-Olguín, C, Alvarez-Lepín, C, Izquierdo, M
Journal of strength and conditioning research. 2013;(8):2219-24
Abstract
The purpose of this study was to examine the effects of a localized muscle endurance resistance training program on total body and regional tissue composition. Seven men and 4 women (aged 23 ± 1 years) were trained with their nondominant leg during 12 weeks, 3 sessions per week. Each session consisted of 1 set of 960-1,200 repetitions (leg press exercise), at 10-30% 1 repetition maximum. Before and after training, body mass, bone mass, bone mineral density (BMD), lean mass, fat mass, and fat percentage were determined by dual-emission x-ray absorptiometry. Energy intakes were registered using a food recall questionnaire. At the whole-body level, body mass, bone mass, BMD, lean mass, or body fat percentage were not significantly changed. However, body fat mass significantly decreased by 5.1% (preexercise: 13.5 ± 6.3 kg; postexercise: 12.8 ± 5.4 kg, p < 0.05). No significant changes in bone mass, lean mass, fat mass, or fat percentage were observed in both the control and trained leg. A significant (p < 0.05) decrease in fat mass was observed in the upper extremities and trunk (10.2 and 6.9%, respectively, p < 0.05). The reduction of fat mass in the upper extremities and trunk was significantly greater (p < 0.05) than the fat mass change observed in the trained leg but not in the control leg. No significant changes were observed in energy intake pre- and postexercise intervention (2,646 ± 444 kcal·d-1 and 2,677 ± 617 kcal·d-1, respectively). In conclusion, the training program was effective in reducing fat mass, but this reduction was not achieved in the trained body segment. The present results expand the limited knowledge available about the plastic heterogeneity of regional body tissues when a localized resistance training program is applied.
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Cardiovascular health profile of elite female football players compared to untrained controls before and after short-term football training.
Randers, MB, Andersen, LJ, Orntoft, C, Bendiksen, M, Johansen, L, Horton, J, Hansen, PR, Krustrup, P
Journal of sports sciences. 2013;(13):1421-31
Abstract
This study examined the intermittent exercise performance and cardiovascular health profile in elite female football players in comparison to untrained young women, as well as a subgroup subjected to football training 2x1 h · week(-1) for 16 weeks. Twenty-seven Danish national team players (elite trained, ET) and 28 untrained women (UT) underwent dual-energy X-ray absorptiometry-scanning (DXA), comprehensive transthoracic echocardiography, treadmill and Yo-Yo Intermittent Endurance level 2 (IE2) testing. Eight women in UT were also tested after the football training period. Maximal oxygen uptake rate (VO2max), peak ventilation and peak lactate were 40, 18 and 51% higher (P< 0.01) in ET than UT, respectively. Cardiac dimensions and function were greater in ET than UT, with left ventricular diastolic diameter, right ventricular diastolic diameter, tricuspid annular plane systolic excursion (TAPSE) and peak transmitral flow in early diastole divided by peak transmitral flow velocity in late diastole during atrial contraction (E/A-ratio) being 13, 19, 27 and 41%, respectively, greater in ET than UT (P< 0.001 to< 0.05). Yo-Yo IE2 performance was 7-fold higher in ET than UT (1772 ± 508 vs. 234 ± 66 m, P< 0.001), fat mass was 51% lower (P< 0.001) and high density lipoprotein (HDL) cholesterol levels were 20% higher (P< 0.01). Sixteen weeks of football elevated VO2max and Yo-Yo IE2 performance by 16 and 40%, respectively, and lowered fat mass by 6%. Cardiac function was markedly improved by 16 weeks of football training with 26 and 46% increases in TAPSE and E/A ratio, respectively, reaching levels comparable to ET. In summary, elite female football players have a superior cardiovascular health profile and intermittent exercise performance compared to untrained controls, but short-term football training can markedly improve the cardiovascular health status.