Adipose Tissue Lipolysis Is Upregulated in Lean and Obese Men During Acute Resistance Exercise

OBJECTIVE—To investigate the effect of acute resistance exercise on adipose tissue triacylglycerol lipase activity (TGLA) in lean and obese men

Intensity of Resistance Exercise Determines Adipokine and Resting Energy Expenditure Responses in Overweight Elderly Individuals

OBJECTIVE - To evaluate the time course of leptin, adiponectin, and testing energy expenditure (REE) responses in overweight elderly mates after acute resistance exercise protocols of various intensity configurations. RESEARCH DESIGN AND METHODS - Forty inactive men (65-82 years) were randomly assigned to one of four groups (n = 10/group): control, low-intensity resistance exercise, moderate-intensity resistance exercise, and high-intensity resistance exercise. Exercise energy cost, REE, leptin, adiponectin, cortisol, insulin, lactate, glucose, nonesterified fatty acids (NEFAs), and glycerol were determined at baseline, immediately after exercise, and during a 72-h recovery period. RESULTS - Exercise energy cost was lower in high-intensity than in low-intensity and moderate-intensity groups (221.6 +/- 8.8 vs. 295.6 +/- 10.7 and 281.6 +/- 9.8 kcal, P < 0.001). Lactate, glucose, NEFAs, and glycerol concentrations increased (P < 0.001) after exercise and returned to baseline thereafter in all groups. REE increased (P < 0.001) in all groups at 12 h in an intensity-dependent manner (P < 0.05). REE reached baseline after 48 h in the low- and mode rate-intensity groups and after 72 h in the high-intensity group. Cortisol peaked in all active groups after exercise (P < 0.001) and remained elevated (P < 0.001) for 12 h. After adjustment for plasma volume shifts, leptin remained unaltered. Adiponectin concentration increased after 12 hand remained elevated for 24 h only in the high-intensity group (P < 0.001). CONCLUSIONS - Resistance exercise does not alter circulating leptin concentration but does increase REE and adiponectin in an intensity-dependent manner for as long as 48 and 24 h, respectively, in overweight elderly individuals. It appears that resistance exercise may represent an effective approach for weight management and metabolic control in overweight elderly individuals

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

The age effects in human physiological adaptation during and oxidative stress exercise

Human aging decreases the factional ability of tissues and reduces the physiological and biochemical adaptations and responses. Sixty-eight male volunteers participated in the present study. They ranged from ages 20-85. All men were healthy and none were athletes. The subjects classified in six different experimental groups according to physical situation and age. Furthermore, physical performance and muscle physiology were evaluated. It was specifically attributed to body composition, leg maximal strength, maximal cardiovascular capacity (VO₂ max), resting blood biochemical’s indices and histochemical muscle analysis. Experimental design anticipates sub-maximal aerobic exercise on a treadmill, with the intensity range from 70-75% VO₂ max, for forty-five minutes and after increased at 90-95% VO₂ max, until exhaustion. Before and after the experimental exercise protocol, venous blood was collected and a muscle biopsy was performed from the quadriceps vastus lateralis. The statistical significant level was defined p<.05, for all experimental factors. The results of the statistical analysis showed that aging decreases the physiological adaptations and responses like the antioxidants defense mechanism, maximal aerobic capacity and muscle physiology and maximal strength. In contrary, acute aerobic exercise, chronic aerobic exercise and high-level physical performance and activity increase the human physiological adaptations and responses and decrease the effects of oxidative damage and stress in all age groups.Η γήρανση του ανθρώπινου οργανισμού σχετίζεται με μια επικείμενη μείωση της λειτουργικής ικανότητας, ελαττώνοντας τις φυσιολογικές, τις βιοχημικές προσαρμογές και αποκρίσεις του. Το δείγμα της μελέτης αποτέλεσαν 68 υγιείς εθελοντές άρρενες (μη αθλητές), ηλικίας 20-85 ετών. Οι δοκιμαζόμενοι κατατάχτηκαν σε 1 από τις 6 πειραματικές ομάδες της μελέτης, ανάλογα με το επίπεδο φυσικής κατάστασης και το παράγοντα ηλικία. Στη συνέχεια εφαρμόστηκαν δοκιμασίες αξιολόγησης φυσικής κατάστασης και φυσιολογικής λειτουργικότητας. Αυτές ήταν σωματομετρικές μετρήσεις, η αξιολόγηση της μέγιστης δύναμης κάτω άκρων, η μέγιστη καρδιοαναπνευστική ικανότητα (VO₂ max), βιοχημικοί δείκτες ηρεμίας, ενώ εφαρμόστηκε και ιστοχημική ανάλυση μυϊκού ιστού. Κατά την πειραματική δοκιμασία εφαρμόστηκε, ήπιας έντασης άσκηση (70-75 % της VO₂ max) για 45 λεπτά, ενώ στη συνέχεια η ένταση αυξήθηκε στο 95 % της VO₂ max, μέχρι εξάντλησης. Πριν και μετά από αυτή τη δοκιμασία συλλέχτηκαν δείγματα αίματος από τη μεσοβασιλική φλέβα και μυϊκού ιστού από τον έξω πλατύ μυ του μηρού. Το επίπεδο σημαντικότητας ορίστηκε στο p<.05 για όλες τις αναλύσεις. Από την ανάλυση των αποτελεσμάτων διακρίνεται μια φθίνουσα μεταβολή των φυσιολογικών προσαρμογών, του αντιοξειδωτικού μηχανισμού, της αερόβιας ικανότητας και της μυϊκής δύναμης, με τη πάροδο των βιολογικών ηλικιακών ετών. Σε αντίθεση με την οξεία αερόβια άσκηση, προκύπτει, ότι η χρόνια αερόβια άσκηση και το ικανοποιητικό επίπεδο φυσικής κατάστασης, δημιουργούν φυσιολογικές προσαρμογές, βελτιώνοντας τις φυσιολογικές αποκρίσεις ενώ παράλληλα μειώνουν τα επίπεδα οξειδωτικού στρες σε όλες τις ηλικιακές ομάδες

Comparison of three protocols for measuring exercise induced muscle soreness

Introduction Delayed-onset muscle soreness (DOMS) has been defined as a form of muscular hyperalgesia and manifests as pain and stiffness in the muscles several hours after strenuous or unaccustomed exercise (Clarkson et al., 1992). Multiple methods exist to assess the perceived soreness, however there are some limitations such as the standardization of the force applied during palpation and the difference of soreness perceived along the length of the muscle (Newham et al., 1983). The aim of this study was to compare different DOMS assessment protocols in their sensitivity to DOMS and other indicators. Methods Three different protocols of evaluating DOMS were compared in response to: a) a football match, b) a basketball match, c) a handball match, d) acute eccentric exercise, e) acute plyometric exercise, f) a weight training bout, g) acute intense running. DOMS and performance (vertical jumping, speed, maximal strength) were measured at baseline, 12 hours post-exercise as well as 1, 2, 3 and 4 days of recovery. The protocols of DOMS evaluated perceived soreness in quadriceps femoris by palpation a) in the standing position (STAN), b) in the sitting (SIT) position and c) in the standing position following three repetitions of a squat movement (SQUAT). Participants in these studies were a) both males and females, b) pre-adolescents, adolescents, adults and elderly and c) trained and sedentary. Results Data analysis revealed that SQUAT produced higher values than the other two DOMS protocols at 24 (for all exercise modes) and 48 hours (for eccentric exercise and plyometric training) of recovery. This difference was more pronounced in sedentary (vs. trained) and older participants (vs. younger adults and pre-adolescents/adolescents). No differences were noted between males and females. A significantly (p<0.05) higher correlation was observed between changes in SQUAT and performance at 24h and 48h than between changes in STAN and SIT. SQUAT produced higher DOMS values following team sports and running as compared to other exercise modes. Discussion The results of this study indicate that DOMS measurement following three squat repetitions may provide a more sensitive measure of muscle damage development following various exercise modes. References Clarkson, P.M., Nosaka, K. & Braun, B. (1992). Muscle function after exercise-induced muscle damage and rapid adaptation

Resistance training and detraining effects on flexibility performance in the elderly are intensity-dependent

The present investigation attempted to determine whether resistance exercise intensity affects flexibility and strength performance in the elderly following a 6-month resistance training and detraining period. Fifty-eight healthy, inactive older men (6578 yrs) were randomly assigned to 1 of 4 groups: a control group (C, n = 10), a low-intensity resistance training group (LI, n = 14, 40% of 1 repetition maximum [1RM]), a moderate-intensity resistance training group (MI, n = 12, 60% of 1RM), or a high-intensity resistance training group (HI, n = 14, 80% of 1RM). Subjects in exercise groups followed a 3 days per week whole-body (10 exercises, 3 sets per exercise) protocol for 24 weeks. Training was immediately followed by a 24-week detraining period. Strength (bench and leg press 1RM) and range of motion in trunk, elbow, knee, shoulder, and hip joints were measured at baseline and during training and detraining. Resistance training increased upper- (34% in LI, 48% in MI, and 75% in HI) and lower-body strength (38% in LI 53% in MI, and 63% in HI) in an intensity-dependent manner. Flexibility demonstrated an intensity-dependent enhancement (3-12% in LI, 6-22% in MI, and 8-28% in HI). Detraining caused significant losses in strength (70-98% in LI, 44-50% in MI, and 27-29% in HI) and flexibility (90-110% in LI, 30-71% in MI, and 23-51% in HI) in an intensity-dependent manner. Results indicate that resistance training by itself improves flexibility in the aged. However, intensities greater than 60% of 1RM are more effective in producing flexibility gains, and strength improvement with resistance training is also intensity-dependent. Detraining seems to reverse training strength and flexibility gains in the elderly in an intensity-dependent manner

A 2-month linear periodized resistance exercise training improved musculoskeletal fitness and specific conditioning of navy cadets

Major objectives of army and navy training are the development of readiness, performance, and injury prevention. Numerous studies have examined the effect of specific strength training (ST) programs on performance of Special Forces and military personnel. Although navy personnel have to address on-board conditions that require the development of strength, agility, speed, and task-specific endurance, there is no information regarding the effects of ST on navy-specific performance. Therefore, the purpose of this study was to investigate the effect of an 8-week ST on performance of navy cadets. Thirty-one cadets of the Hellenic Naval Academy volunteered to participate and were randomly assigned in 2 groups. Cadets in the Experimental Group participated in a linear periodized ST program in addition to their daily training schedule. Cadets in the control group participated only in pre-and post-measurements. Anthropometrics, maximal oxygen consumption, oxygen consumption during a Navy Obstacle Course (NOC), maximum strength in bench press and squat exercises, hand grip strength, repetitions in push-ups and abdominal test, time to complete a 30-m sprint, and time to complete NOC were measured before and after the intervention. A 2-way repeated-measures analysis of variance showed that ST induced favorable changes in bench press and squat 1 repetition maximum, push-ups, abdominal crunches, time to complete 30-m distance, and time to complete the NOC. These results indicate that an additional ST may induce positive alterations on readiness and performance of navy cadets. The study has the approval of university's institutional review board and ethical committee. © 2017 National Strength and Conditioning Association