The effects of acute low-volume HIIT and aerobic exercise on leukocyte count and redox status

A single bout of exercise can result in inflammatory responses, increased oxidative stress and upregulation of enzymatic antioxidant mechanisms. Although low-volume high-intensity interval training (HIIT) has become popular, its acute responses on the above mechanisms have not been adequately studied. The present study evaluated the effects of HIIT on hematological profile and redox status compared with those following traditional continuous aerobic exercise (CET). Twelve healthy young men participated in a randomized crossover design under HIIT and CET. In HIIT session, participants performed four 30-sec sprints on a cycle-ergometer with 4 min of recovery against a resistance of 0.375 kg/kg of body mass. CET consisted of 30-min cycling on a cycle-ergometer at 70% of their VO2max. Blood was drawn at baseline, immediately post, 24h, 48h and 72h post-exercise and was analyzed for complete blood count and redox status (thiobarbituric acid reactive substances, [TBARS]; protein carbonyls, [PC]; total antioxidant capacity, [TAC]; catalase and uric acid). White blood cells (WBC) increased after both exercise protocols immediately post-exercise (HIIT: 50% and CET: 31%, respectively). HIIT increased (+22%) PC post-exercise compared to baseline and CET (p 0.05) for TBARS and catalase following either exercise protocol. Low-volume HIIT is associated with a greater acute phase leukocyte count and redox response than low-volume CET, and this should be considered when an exercise training program is developed and complete blood count is performed for health purposes

Evidence of a Redox-Dependent Regulation of Immune Responses to Exercise-Induced Inflammation

We used thiol-based antioxidant supplementation (n-acetylcysteine, NAC) to determine whether immune mobilisation following skeletal muscle microtrauma induced by exercise is redox-sensitive in healthy humans. According to a two-trial, double-blind, crossover, repeated measures design, 10 young men received either placebo or NAC (20 mg/kg/day) immediately after a muscle-damaging exercise protocol (300 eccentric contractions) and for eight consecutive days. Blood sampling and performance assessments were performed before exercise, after exercise, and daily throughout recovery. NAC reduced the decline of reduced glutathione in erythrocytes and the increase of plasma protein carbonyls, serum TAC and erythrocyte oxidized glutathione, and TBARS and catalase activity during recovery thereby altering postexercise redox status. The rise of muscle damage and inflammatory markers (muscle strength, creatine kinase activity, CRP, proinflammatory cytokines, and adhesion molecules) was less pronounced in NAC during the first phase of recovery. The rise of leukocyte and neutrophil count was decreased by NAC after exercise. Results on immune cell subpopulations obtained by flow cytometry indicated that NAC ingestion reduced the exercise-induced rise of total macrophages, HLA+ macrophages, and 11B+ macrophages and abolished the exercise-induced upregulation of B lymphocytes. Natural killer cells declined only in PLA immediately after exercise. These results indicate that thiol-based antioxidant supplementation blunts immune cell mobilisation in response to exercise-induced inflammation suggesting that leukocyte mobilization may be under redox-dependent regulation

Disparate habitual physical activity and dietary intake profiles of elderly men with low and elevated systemic inflammation

The development of chronic, low-grade systemic inflammation in the elderly (inflammaging) has been associated with increased incidence of chronic diseases, geriatric syndromes, and functional impairments. The aim of this study was to examine differences in habitual physical activity (PA), dietary intake patterns, and musculoskeletal performance among community-dwelling elderly men with low and elevated systemic inflammation. Nonsarcopenic older men free of chronic diseases were grouped as ‘low’ (LSI: n = 17; 68.2 ± 2.6 years; hs-CRP: 1 mg/L) systemic inflammation according to their serum levels of high-sensitivity CRP (hs-CRP). All participants were assessed for body composition via Dual Emission X-ray Absorptiometry (DEXA), physical performance using the Short Physical Performance Battery (SPPB) and handgrip strength, daily PA using accelerometry, and daily macro- and micronutrient intake. ESI was characterized by a 2-fold greater hs-CRP value than LSI (p < 0.01). The two groups were comparable in terms of body composition, but LSI displayed higher physical performance (p < 0.05), daily PA (step count/day and time at moderate-to-vigorous PA (MVPA) were greater by 30% and 42%, respectively, p < 0.05), and daily intake of the antioxidant vitamins A (6590.7 vs. 4701.8 IU/day, p < 0.05), C (120.0 vs. 77.3 mg/day, p < 0.05), and E (10.0 vs. 7.5 mg/day, p < 0.05) compared to ESI. Moreover, daily intake of vitamin A was inversely correlated with levels of hs-CRP (r = −0.39, p = 0.035). These results provide evidence that elderly men characterized by low levels of systemic inflammation are more physically active, spend more time in MVPA, and receive higher amounts of antioxidant vitamins compared to those with increased systemic inflammation

Recovery kinetics of knee flexor and extensor strength after a football match

© 2015 The Authors. Published by PLOS. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0128072We examined the temporal changes of isokinetic strength performance of knee flexor (KF) and extensor (KE) strength after a football match. Players were randomly assigned to a control (N = 14, participated only in measurements and practices) or an experimental group (N = 20, participated also in a football match). Participants trained daily during the two days after the match. Match and training overload was monitored with GPS devices. Venous blood was sampled and muscle damage was assessed pre-match, post-match and at 12h, 36h and 60h post-match. Isometric strength as well as eccentric and concentric peak torque of knee flexors and extensors in both limbs (dominant and non-dominant) were measured on an isokinetic dynamometer at baseline and at 12h, 36h and 60h after the match. Functional (KFecc/KEcon) and conventional (KFcon/KEcon) ratios were then calculated. Only eccentric peak torque of knee flexors declined at 60h after the match in the control group. In the experimental group: a) isometric strength of knee extensors and knee flexors declined (P<0.05) at 12h (both limbs) and 36h (dominant limb only), b) eccentric and concentric peak torque of knee extensors and flexors declined (P<0.05) in both limbs for 36h at 60°/s and for 60h at 180°/s with eccentric peak torque of knee flexors demonstrating a greater (P<0.05) reduction than concentric peak torque, c) strength deterioration was greater (P<0.05) at 180°/s and in dominant limb, d) the functional ratio was more sensitive to match-induced fatigue demonstrating a more prolonged decline. Discriminant and regression analysis revealed that strength deterioration and recovery may be related to the amount of eccentric actions performed during the match and athletes' football-specific conditioning. Our data suggest that recovery kinetics of knee flexor and extensor strength after a football match demonstrate strength, limb and velocity specificity and may depend on match physical overload and players' physical conditioning level.Published versio

Η επίδραση της φλεγμονής στην αναβολική κατάσταση και στον μηχανισμό πρωτεόλυσης του σκελετικού μυ ηλικιωμένων ατόμων

Introduction: The development of chronic, low-grade systemic inflammation in the elderly (inflammaging) has been shown to increase the risk for chronic diseases and geriatric syndromes while it has been also associated with accelerated skeletal muscle wasting, strength loss and functional impairments.Aim: The aim of the present thesis was i) to examine whether anabolic signaling, activation of amino acid transporters, ribosome biogenesis and proteasome activity in the aged skeletal muscle are affected by low-grade systemic inflammation in the fasted state and following exercise and protein feeding, and ii) to investigate differences in habitual physical activity, dietary intake, physical performance and blood indices of oxidative stress and antioxidant status among elderly men with low and elevated low-grade systemic inflammation.Methods: Forty-four male adults aged 63-75 years who complied with the inclusion criteria were included in the study. Initially they were screened for systemic levels of hs-CRP and then had their anthropometric profile, body composition, sarcopenia status and functional performance assessed. Habitual physical activity and daily dietary intake were assessed over a 7-day period using accelerometry and diet recalls, respectively. Of these 44 individuals, 12 with high systemic inflammation (HSI: hs-CRP: > 1.0 mg/L) and 12 with low (LSI: hs-CRP: ≤ 1.0 mg/L) were included in the clinical trial. On the experimental day, participants performed 8 sets of 10 repetitions at 70% of 1RM on a knee-extension machine and immediately after they ingested a whey protein bolus. Muscle biopsy samples were collected before exercise (fasted state) and at 3h following protein ingestion. Blood samples were collected before exercise and every 30 minutes during the 3-hour postprandial period.Results: In the fasted state, HSI exhibited higher chymotrypsin-like activity, protein carbonyl concentration and phosphorylated IKKα/β, by 40%, 47% and 37%, respectively, as compared to LSI (P 1.0 mg/L) και 12 με χαμηλή (χαμηλή ΧΣΦ: hs-CRP: ≤ 1.0 mg/L) έλαβαν μέρος στην κλινική δοκιμασία. Την ημέρα της κλινικής δοκιμασίας, οι συμμετέχοντες εκτέλεσαν 8 σετ των 10 επαναλήψεων στο 70% της 1ΜΕ στο μηχάνημα εκτάσεις γονάτων και αμέσως μετά κατανάλωναν συμπλήρωμα πρωτεΐνης ορού γάλακτος, σε μία δόση. Δείγματα μυός (μυϊκές βιοψίες) συλλέχθηκαν πριν την άσκηση (σε κατάσταση νηστείας) καθώς και στις 3 ώρες μετά τη λήψη του συμπληρώματος πρωτεΐνης. Αιμοληψίες πραγματοποιήθηκαν πριν την άσκηση και κάθε 30 λεπτά για 3 ώρες μετά την κατανάλωση του συμπληρώματος πρωτεΐνης.Αποτελέσματα: Στην κατάσταση νηστείας , η ομάδα υψηλής ΧΣΦ παρουσίασε υψηλότερη ενεργότητα χυμοθρυψίνης, μεγαλύτερη συγκέντρωση πρωτεϊνικών καρβονυλίων και μεγαλύτερη ποσότητα φωσφορυλιωμένης κινάσης ΙΚΚα/β, κατά 40%, 47% και 37%, αντίστοιχα, σε σύγκριση με την ομάδα χαμηλής ΧΣΦ (P < 0.05). Δεν παρατηρήθηκαν διαφορές μεταξύ των δύο ομάδων όσον αφορά την ενεργότητα τρυψίνης, την έκφραση των β υπομονάδων του πρωτεασώματος και του ανοσοπρωτεασώματος, τα επίπεδα του Nrf2 στον πυρήνα καθώς και τα επίπεδα 3-νιτροτυροσίνης. Επίσης, σημαντική συσχέτιση εντοπίστηκε μεταξύ των επιπέδων hs-CRP και της ενεργότητας χυμοθρυψίνης (P < 0.05) σε κατάσταση νηστείας. Στις 3 ώρες μετά την κατανάλωση του συμπληρώματος πρωτεΐνης, η ενεργότητα χυμοθρυψίνης αυξήθηκε σημαντικά και στις δυο ομάδες (υψηλή ΧΣΦ: +44%, χαμηλή ΧΣΦ: +86%, P < 0.05), χωρίς να διαφέρουν μεταξύ τους, ενώ η ενεργότητα της τρυψίνης αυξήθηκε μόνο στην ομάδα χαμηλής ΧΣΦ κατά 38% (P < 0.05). Η συγκέντρωση πρωτεϊνικών καρβονυλίων μειώθηκε κατά 31% στην ομάδα υψηλής ΧΣΦ (P < 0.05), ενώ τα επίπεδα του Nrf2 αυξήθηκαν σημαντικά μόνο την ομάδα χαμηλής ΧΣΦ (+28%, P < 0.05). Η έκφραση των β υπομονάδων του πρωτεασώματος και των αντίστοιχων βi του ανοσοπρωτεασώματος καθώς και τα επίπεδα 3-νιτροτυροσίνης και φωσφορυλιωμένης κινάσης ΙΚΚα/β παρέμειναν αμετάβλητα μετά την κατανάλωση της πρωτεΐνης. Επιπλέον, η φωσφορυλίωση της ριβοσωμικής πρωτεΐνης rpS6 αυξήθηκε σημαντικά στις 3 ώρες μετά τη λήψη του συμπληρώματος πρωτεΐνης μόνο στην ομάδα χαμηλής ΧΣΦ (+ 1.5 φορά, P < 0.05) και τα επίπεδά της διέφεραν σημαντικά από εκείνα της ομάδας υψηλής ΧΣΦ (P < 0.05). Η έκφραση των μεταφορέων αμινοξέων αλλά και η ενεργοποίηση δεικτών ριβοσωμικής βιογένεσης δεν παρουσίασαν σημαντικές μεταβολές σε καμία απ’ τις δυο ομάδες. Οι δυο ομάδες ωστόσο, διέφεραν σημαντικά μεταξύ τους όσον αφορά τα επίπεδα φυσικής δραστηριότητας, με την ομάδα χαμηλής ΧΣΦ να εκτελεί περισσότερα βήματα (+ 30%, P < 0.05) και να δαπανά περισσότερο χρόνο σε μέτρια-προς-υψηλής έντασης δραστηριότητες (+ 42%, P < 0.05) σε σύγκριση με την ομάδα υψηλής ΧΣΦ. Επίσης, η ομάδα χαμηλής ΧΣΦ παρουσίασε υψηλότερη πρόσληψη αντιοξειδωτικών βιταμινών σε σχέση με την ομάδα υψηλής ΧΣΦ (P < 0.05)η οποία συνοδευόταν και από υψηλότερη αντιοξειδωτική ικανότητα στο πλάσμα (+ 60%, P < 0.05). Συμπεράσματα: Τα αποτελέσματα της παρούσας διατριβής υποδεικνύουν ότι τα ηλικιωμένα άτομα με υψηλή ΧΣΦ χαρακτηρίζονται από αυξημένα επίπεδα οξειδωμένων πρωτεϊνών και αυξημένη ενεργοποίηση του πρωτεολυτικού μηχανισμού του πρωτεασώματος στο μυ, σε κατάσταση νηστείας, καθώς επίσης και από μειωμένη μεταφραστική δραστηριότητα στο ριβόσωμα, στη μεταγευματική περίοδο. Επιπλέον, μεγαλύτερα επίπεδα φυσικής δραστηριότητας σε ημερήσια βάση και μεγαλύτερη πρόσληψη αντιοξειδωτικών βιταμινών μέσω της διατροφής φαίνεται ότι διαφοροποιούν τα άτομα με χαμηλή και υψηλή ΧΣΦ, και επομένως θα πρέπει θεωρούνται καθοριστικοί παράγοντες για την υγεία στα άτομα τρίτης ηλικίας, οι οποίοι μπορούν να επιδράσουν ανασταλτικά στην εκδήλωση ΧΣΦ

Exercise-Induced Regulation of Redox Status in Cardiovascular Diseases: The Role of Exercise Training and Detraining

Although low levels of reactive oxygen species (ROS) are beneficial for the organism ensuring normal cell and vascular function, the overproduction of ROS and increased oxidative stress levels play a significant role in the onset and progression of cardiovascular diseases (CVDs). This paper aims at providing a thorough review of the available literature investigating the effects of acute and chronic exercise training and detraining on redox regulation, in the context of CVDs. An acute bout of either cardiovascular or resistance exercise training induces a transient oxidative stress and inflammatory response accompanied by reduced antioxidant capacity and enhanced oxidative damage. There is evidence showing that these responses to exercise are proportional to exercise intensity and inversely related to an individual&rsquo;s physical conditioning status. However, when chronically performed, both types of exercise amplify the antioxidant defense mechanism, reduce oxidative stress and preserve redox status. On the other hand, detraining results in maladaptations within a time-frame that depends on the exercise training intensity and mode, as high-intensity training is superior to low-intensity and resistance training is superior to cardiovascular training in preserving exercise-induced adaptations during detraining periods. Collectively, these findings suggest that exercise training, either cardiovascular or resistance or even a combination of them, is a promising, safe and efficient tool in the prevention and treatment of CVDs

Ingestion of a Pre-bedtime Protein Containing Beverage Prevents Overnight Induced Negative Whole Body Protein Balance in Healthy Middle-Aged Men: A Randomized Trial.

Age related muscle wasting leads to overall reductions of lean body mass, reduced muscle strength, and muscle function resulting in compromised quality of life. Utilizing novel nutritional strategies to attenuate such losses is of great importance in elderly individuals. We aimed to test if a complete dietary supplement containing 25 g of milk proteins and ingested in the evening before bed would improve protein metabolism in terms of whole body protein balance over a 10 h overnight period following ingestion of the test drink in healthy middle-aged male subjects. In addition we also assessed the rates of muscle protein synthesis during the second half of the night in order to see if previously reported extended amino acidemia during sleep results in increased rates of muscle protein synthesis. Seventeen healthy middle-aged male subjects (59.4 ± 3.2 year) consumed a dietary supplement drink at 21:00 containing either 25 g milk protein concentrate, 25 g maltodextrin, 7.75 g canola oil (treatment group), or an isocaloric protein void drink (placebo group). Muscle protein synthesis was assessed from a muscle biopsy following the continuous intravenous infusion of 13C-phenylalanine for 5 h (from 03:00 to 08:00). Whole body protein balance was greater in the treatment group (-0.13 ± 11.30 g prot/10 h) compared to placebo (-12.22 ± 6.91 g prot/10 h) (P ≤ 0.01). In contrast, no changes were observed on rates of muscle protein synthesis during the second half of the night. Ingestion of a dietary supplement containing 25 g of milk proteins significantly reduced the negative protein balance observed during the night. Therefore, pre-bedtime protein ingestion may attenuate overnight losses of lean tissue in healthy elderly men. Despite increases in aminoacidemia during the second part of the night, no changes were observed in the rates of muscle protein synthesis during this time. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02041143

Exercise in Glucose-6-Phosphate Dehydrogenase Deficiency: Harmful or Harmless? A Narrative Review

Objectives. Glucose-6-phosphate dehydrogenase (G6PD) deficiency, theoretically, renders red blood cells (RBC) susceptible to oxidative stress. G6PD deficiency has also been found in other types of cells than RBC, such as leukocytes and myocytes, where an inefficient protection against oxidative stress may occur too. Glutathione (GSH), a significant antioxidant molecule, levels are lower in G6PD individuals, and theoretically, the probability of oxidative stress and haemolysis due to exercise in individuals with G6PD deficiency is increased, whereas dietary supplementation with antioxidants may have beneficial effects on various aspects of this enzymopathy. Methods. A search of the available literature was conducted using the keywords glucose-6-phosphate dehydrogenase (G6PD), deficiency, disease, exercise, muscle, antioxidant, vitamin, supplement, and supplementation. The search was limited to publications in English, conducted on humans, and published until August 2018. After screening, only relevant articles were included. Results. There is little evidence indicating that G6PD deficiency can cause perturbations in redox status, haemolysis, and clinical symptoms such as fatigability and myoglobinuria, especially after intense exercise, compared to individuals with normal enzyme levels. Conclusions. Exercise could be used by G6PD-deficient individuals as a tool to improve their quality of life. However, there is a lack of training studies, and assessment of the effects of regular and systematic exercise in G6PD-deficient individuals is warranted. Finally, since GSH levels are lower in G6PD deficiency, it would be interesting to examine the effects of antioxidant or cysteine donor supplements on redox status after exercise in these individuals