Evidence of the effectiveness of zinc (Zn) and selenium (Se) on resting metabolic rate (RMR) and ... more Evidence of the effectiveness of zinc (Zn) and selenium (Se) on resting metabolic rate (RMR) and physical function parameters in people with overweight and obesity is scarce, while the effects of zinc and selenium on thyroid function and body composition are still a topic of debate and controversy. The aim of this randomized, double-blind, and placebo-controlled trial was to examine the effects of a hypocaloric diet and Se–Zn co-supplementation on RMR, thyroid function, body composition, physical fitness, and functional capacity in overweight or obese individuals. Twenty-eight overweight–obese participants (mean BMI: 29.4 ± 4.7) were randomly allocated (1:1) to the supplementation group (n = 14, 31.1 ± 5.5 yrs, 9 females) and the placebo group (n = 14, 32.1 ± 4.8 yrs, 6 females). The participants received Zn (25 mg of zinc gluconate/day) and Se (200 mcg of L-selenomethionine/day) or placebo tablets containing starch for eight weeks. The participants of both groups followed a hypocal...
BackgroundThe world’s population is aging, but life expectancy has risen more than healthy life e... more BackgroundThe world’s population is aging, but life expectancy has risen more than healthy life expectancy (HALE). With respect to brain and cognition, the prevalence of neurodegenerative disorders increases with age, affecting health and quality of life, and imposing significant healthcare costs. Although the effects of physical exercise on cognition in advanced age have been widely explored, in-depth fundamental knowledge of the underlying mechanisms of the exercise-induced cognitive improvements is lacking. Recent research suggests that myokines, factors released into the blood circulation by contracting skeletal muscle, may play a role in mediating the beneficial effect of exercise on cognition. Our goal in this ongoing (living) review is to continuously map the rapidly accumulating knowledge on pathways between acute or chronic exercise-induced myokines and cognitive domains enhanced by exercise.MethodRandomized controlled studies will be systematically collected at baseline an...
BACKGROUND The exact causes of skeletal muscle weakness in chronic kidney disease (CKD) remain un... more BACKGROUND The exact causes of skeletal muscle weakness in chronic kidney disease (CKD) remain unknown with uremic toxicity and redox imbalances being implicated. To understand whether uremic muscle has acquired any sensitivity to acute redox changes we examined the effects of redox disturbances on force generation capacity. METHODS Permeabilized single psoas fibers (N =37) from surgically induced CKD (UREM) and sham-operated (CON) rabbits were exposed to an oxidizing (10 mM Hydrogen Peroxide, H2O2) and/or a reducing [10 mM Dithiothreitol (DTT)] agent, in a blind design, in two sets of experiments examining: A) the acute effect of the addition of H2O2 on maximal (pCa 4.4) isometric force of actively contracting fibers and the effect of incubation in DTT on subsequent re-activation and force recovery (N =9 CON; N =9 UREM fibers); B) the effect of incubation in H2O2 on both submaximal (pCa 6.2) and maximal (pCa 4.4) calcium activated isometric force generation (N =9 CON; N =10 UREM fi...
Ο μυϊκός κάματος eίναι ένα γνώριμο φαινόμeνο που παρατηρeίται τόσο στον αθλητισμό όσο και στην κα... more Ο μυϊκός κάματος eίναι ένα γνώριμο φαινόμeνο που παρατηρeίται τόσο στον αθλητισμό όσο και στην καθημeρινότητα υγιών ατόμων και ασθeνών μe χρόνιeς παθήσeις. Ωστόσο, οι μηχανισμοί ρύθμισής του eίναι ιδιαίτeρα πeρίπλοκοι και πeριλαμβάνουν πολλά στάδια, από το κeντρικό νeυρικό σύστημα έως και την καθαυτή αλληλeπίδραση των κινητικών πρωτeϊνών, της μυοσίνης μe την ακτίνη. Στην παρούσα βιβλιογραφική ανασκόπηση παρουσιάζονται οι παράγοντeς που eπιδρούν απeυθeίας στην αλληλeπίδραση της μυοσίνης μe την ακτίνη και γίνeται σύνδeση μe τις eκφάνσeις του καμάτου σe λeιτουργικό eπίπeδο. Eπιπλέον γίνeται σύντομη σύνδeση μe την αθλητική απόδοση σe υγιή άτομα και τη λeιτουργική ικανότητα χρόνια πασχόντων. Λέξeις κλeιδιά: Μυϊκή κόπωση, σαρκομeρικές πρωτeΐνeς, απομeμβρανωμένeς ίνeς, κύκλος της eγκάρσιας γέφυρας, συσταλτικές ιδιότητeς
Purpose To compare physical, psychological, and physiological adaptations between rotating and mo... more Purpose To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Methods Forty nurses [ n = 20 morning shift (MS) group; n = 20 rotating shift (RS) group] were evaluated for anthropometry, body composition, and handgrip strength. Quality of life, depression, fatigue, daytime sleepiness, and sleep quality were assessed with SF-36, Zung Self-Rating Depression Scale (SDS), Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI), respectively. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ) and triaxial accelerometers. Sleep-related data were monitored with sleep actigraphy. Salivary melatonin levels were analyzed before/after sleep, and blood lipid profiles were measured the following morning. Results The RS group had higher mean BMI and total and abdominal fat and scored lower in the SF-36 ( p < 0.01). All nurses showed reduced physical activity levels, which, in the RS group, were negatively correlated with FSS ( p = 0.033) and SDS scores ( p = 0.025). Poor sleep was revealed in 53% of nurses. The RS group had worse sleep quality by PSQI than the MS group ( p = 0.045). PSQI scores were inversely related to SF-36 scores and positively correlated with FSS, BMI, waist circumference, and body fat ( p < 0.05). Conclusion RS nurses showed increased body mass and total and abdominal fat along with decreased quality of life and sleep quality compared to MS counterparts. A strong relationship was found between physical, psychological, and physiological domains. Further studies should consider workplace interventions to prevent obesity, promote physical activity, and manage poor sleeping patterns in nurses.
Purpose Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and mus... more Purpose Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and muscle atrophy, all leading to generalized fatigue and lack of energy. HD patients spend at least 50% of their time in a functionally “switch off” mode with their fatigue sensations reaching a peak in the immediate hours after the dialysis session. The purpose of the current study was to assess the effectiveness of a nine-month hybrid intradialytic exercise program on fatigue symptoms occurring during and after hemodialysis session. Methods Twenty stable hemodialysis patients were included in the study (59 ± 13.7 years; 16 males). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training during HD. Aspects related to physical and generalized fatigue were assessed via validated questionnaires, while physical performance was assessed by a battery of tests, before and after the intervention period. Results Exercise capacity and physical performance were increased by an average of 65 and 40%, respectively. Patients reported feeling better during post-dialysis hours in question 1 ( p = 0.000), question 3 ( p = 0.009) and question 4 ( p = 0.003) after the 9-month intervention. In addition, exercise training improved scores in cognitive function ( p = 0.037), vitality ( p = 0.05), depression ( p = 0.000) and fatigue ( p = 0.039). Conclusion The present study showed that a 9-month hybrid (aerobic + resistance) exercise training program improved symptoms of post-dialysis fatigue and overall general perception of fatigue. Hybrid exercise training is a safe and effective non-pharmacological approach to ameliorate fatigue symptoms in HD patients. Trial registration number Trial registration number The study is registered at ClinicalTrials.gov (NCT01721551, 2012) as a clinical trial.
Evidence of the effectiveness of zinc (Zn) and selenium (Se) on resting metabolic rate (RMR) and ... more Evidence of the effectiveness of zinc (Zn) and selenium (Se) on resting metabolic rate (RMR) and physical function parameters in people with overweight and obesity is scarce, while the effects of zinc and selenium on thyroid function and body composition are still a topic of debate and controversy. The aim of this randomized, double-blind, and placebo-controlled trial was to examine the effects of a hypocaloric diet and Se–Zn co-supplementation on RMR, thyroid function, body composition, physical fitness, and functional capacity in overweight or obese individuals. Twenty-eight overweight–obese participants (mean BMI: 29.4 ± 4.7) were randomly allocated (1:1) to the supplementation group (n = 14, 31.1 ± 5.5 yrs, 9 females) and the placebo group (n = 14, 32.1 ± 4.8 yrs, 6 females). The participants received Zn (25 mg of zinc gluconate/day) and Se (200 mcg of L-selenomethionine/day) or placebo tablets containing starch for eight weeks. The participants of both groups followed a hypocal...
BackgroundThe world’s population is aging, but life expectancy has risen more than healthy life e... more BackgroundThe world’s population is aging, but life expectancy has risen more than healthy life expectancy (HALE). With respect to brain and cognition, the prevalence of neurodegenerative disorders increases with age, affecting health and quality of life, and imposing significant healthcare costs. Although the effects of physical exercise on cognition in advanced age have been widely explored, in-depth fundamental knowledge of the underlying mechanisms of the exercise-induced cognitive improvements is lacking. Recent research suggests that myokines, factors released into the blood circulation by contracting skeletal muscle, may play a role in mediating the beneficial effect of exercise on cognition. Our goal in this ongoing (living) review is to continuously map the rapidly accumulating knowledge on pathways between acute or chronic exercise-induced myokines and cognitive domains enhanced by exercise.MethodRandomized controlled studies will be systematically collected at baseline an...
BACKGROUND The exact causes of skeletal muscle weakness in chronic kidney disease (CKD) remain un... more BACKGROUND The exact causes of skeletal muscle weakness in chronic kidney disease (CKD) remain unknown with uremic toxicity and redox imbalances being implicated. To understand whether uremic muscle has acquired any sensitivity to acute redox changes we examined the effects of redox disturbances on force generation capacity. METHODS Permeabilized single psoas fibers (N =37) from surgically induced CKD (UREM) and sham-operated (CON) rabbits were exposed to an oxidizing (10 mM Hydrogen Peroxide, H2O2) and/or a reducing [10 mM Dithiothreitol (DTT)] agent, in a blind design, in two sets of experiments examining: A) the acute effect of the addition of H2O2 on maximal (pCa 4.4) isometric force of actively contracting fibers and the effect of incubation in DTT on subsequent re-activation and force recovery (N =9 CON; N =9 UREM fibers); B) the effect of incubation in H2O2 on both submaximal (pCa 6.2) and maximal (pCa 4.4) calcium activated isometric force generation (N =9 CON; N =10 UREM fi...
Ο μυϊκός κάματος eίναι ένα γνώριμο φαινόμeνο που παρατηρeίται τόσο στον αθλητισμό όσο και στην κα... more Ο μυϊκός κάματος eίναι ένα γνώριμο φαινόμeνο που παρατηρeίται τόσο στον αθλητισμό όσο και στην καθημeρινότητα υγιών ατόμων και ασθeνών μe χρόνιeς παθήσeις. Ωστόσο, οι μηχανισμοί ρύθμισής του eίναι ιδιαίτeρα πeρίπλοκοι και πeριλαμβάνουν πολλά στάδια, από το κeντρικό νeυρικό σύστημα έως και την καθαυτή αλληλeπίδραση των κινητικών πρωτeϊνών, της μυοσίνης μe την ακτίνη. Στην παρούσα βιβλιογραφική ανασκόπηση παρουσιάζονται οι παράγοντeς που eπιδρούν απeυθeίας στην αλληλeπίδραση της μυοσίνης μe την ακτίνη και γίνeται σύνδeση μe τις eκφάνσeις του καμάτου σe λeιτουργικό eπίπeδο. Eπιπλέον γίνeται σύντομη σύνδeση μe την αθλητική απόδοση σe υγιή άτομα και τη λeιτουργική ικανότητα χρόνια πασχόντων. Λέξeις κλeιδιά: Μυϊκή κόπωση, σαρκομeρικές πρωτeΐνeς, απομeμβρανωμένeς ίνeς, κύκλος της eγκάρσιας γέφυρας, συσταλτικές ιδιότητeς
Purpose To compare physical, psychological, and physiological adaptations between rotating and mo... more Purpose To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Methods Forty nurses [ n = 20 morning shift (MS) group; n = 20 rotating shift (RS) group] were evaluated for anthropometry, body composition, and handgrip strength. Quality of life, depression, fatigue, daytime sleepiness, and sleep quality were assessed with SF-36, Zung Self-Rating Depression Scale (SDS), Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and Pittsburgh Sleep Quality Index (PSQI), respectively. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ) and triaxial accelerometers. Sleep-related data were monitored with sleep actigraphy. Salivary melatonin levels were analyzed before/after sleep, and blood lipid profiles were measured the following morning. Results The RS group had higher mean BMI and total and abdominal fat and scored lower in the SF-36 ( p < 0.01). All nurses showed reduced physical activity levels, which, in the RS group, were negatively correlated with FSS ( p = 0.033) and SDS scores ( p = 0.025). Poor sleep was revealed in 53% of nurses. The RS group had worse sleep quality by PSQI than the MS group ( p = 0.045). PSQI scores were inversely related to SF-36 scores and positively correlated with FSS, BMI, waist circumference, and body fat ( p < 0.05). Conclusion RS nurses showed increased body mass and total and abdominal fat along with decreased quality of life and sleep quality compared to MS counterparts. A strong relationship was found between physical, psychological, and physiological domains. Further studies should consider workplace interventions to prevent obesity, promote physical activity, and manage poor sleeping patterns in nurses.
Purpose Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and mus... more Purpose Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and muscle atrophy, all leading to generalized fatigue and lack of energy. HD patients spend at least 50% of their time in a functionally “switch off” mode with their fatigue sensations reaching a peak in the immediate hours after the dialysis session. The purpose of the current study was to assess the effectiveness of a nine-month hybrid intradialytic exercise program on fatigue symptoms occurring during and after hemodialysis session. Methods Twenty stable hemodialysis patients were included in the study (59 ± 13.7 years; 16 males). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training during HD. Aspects related to physical and generalized fatigue were assessed via validated questionnaires, while physical performance was assessed by a battery of tests, before and after the intervention period. Results Exercise capacity and physical performance were increased by an average of 65 and 40%, respectively. Patients reported feeling better during post-dialysis hours in question 1 ( p = 0.000), question 3 ( p = 0.009) and question 4 ( p = 0.003) after the 9-month intervention. In addition, exercise training improved scores in cognitive function ( p = 0.037), vitality ( p = 0.05), depression ( p = 0.000) and fatigue ( p = 0.039). Conclusion The present study showed that a 9-month hybrid (aerobic + resistance) exercise training program improved symptoms of post-dialysis fatigue and overall general perception of fatigue. Hybrid exercise training is a safe and effective non-pharmacological approach to ameliorate fatigue symptoms in HD patients. Trial registration number Trial registration number The study is registered at ClinicalTrials.gov (NCT01721551, 2012) as a clinical trial.
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