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1.
J Strength Cond Res ; 36(11): 3217-3223, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165989

RESUMO

ABSTRACT: Wadsworth, DD, Rodriguez-Hernandez, M, Huffman, LS, McDonald, JR, Spring, KE, and Pascoe, DD. Adaptations to a concurrent exercise training program in inactive aging women. J Strength Cond Res 36(11): 3217-3223, 2022-This study assessed the effect of a 10-week, sprint interval concurrent exercise training program on body composition and muscular strength in aging women. Sixty-five inactive women (age, 40-64 years) were randomized into 2 sprint interval exercise programs, 0% incline and 6% incline. Sprint interval training was performed to achieve 95% of each subject's age-predicted maximal heart rate for a series of 40 seconds of work followed by 20 seconds of passive recovery. An undulating resistance training protocol, composed of 30 sessions, was performed by each group throughout the study. Dual-energy X-ray absorption scans were assessed body composition, and 1 repetition maximum was performed to assess muscular strength. Subjects in both groups significantly reduced fat mass by approximately 0.35 kg ( p = 0.002), and visceral adipose tissue by 0.05 kg ( p = 0.032). There were significant increases in lean body mass by approximately 0.50 kg ( p = 0.005), lower-body muscular strength by approximately 46.83 kg ( p < 0.001), and upper-body muscular strength by approximately 11.68 kg ( p < 0.001). No significant between-groups interactions were observed. A sprint interval training concurrent exercise training program is an effective strategy to improve body composition and muscular strength in inactive, aging women. Muscular strength improvements resulting from this intervention are particularly important because muscular strength losses are strong predictors of morbidity and mortality.


Assuntos
Treinamento Intervalado de Alta Intensidade , Treinamento Resistido , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Treinamento Resistido/métodos , Força Muscular/fisiologia , Exercício Físico/fisiologia , Composição Corporal/fisiologia , Envelhecimento
2.
Eur J Appl Physiol ; 120(2): 369-380, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31813045

RESUMO

PURPOSE: We investigated the effect of ischemic preconditioning (IPC) on performance of a 3 min maximal effort arm ergometer test in young women. METHODS: Twenty healthy women (23.1 (SD 3.3) years) performed a 3 min maximal effort arm cycling exercise, preceded by IPC on both arms or SHAM in a counterbalanced randomized crossover design. Both blood flow (via high resolution ultrasound; n = 17) and muscle oxygenation/deoxygenation (via near infrared spectroscopy; n = 5) were measured throughout the IPC/SHAM. Performance and perceptual/physiological (i.e., heart rate, blood lactate, rating of perceived exertion, and triceps brachialis oxygenation) parameters were recorded during the exercise test. RESULTS: Occlusion during IPC completely blocked brachial artery blood flow, decreased oxygenated hemoglobin/myoglobin (Δ[oxy(Hb + Mb)]), and increased deoxygenated Hb/Mb (Δ[deoxy(Hb + Mb)]). There were no differences (P > 0.797) in performance (peak, mean, and end power output) or in any perceptual/physiological variables during the 3 min all-out test between IPC/SHAM. During exercise, Δ[oxy(Hb + Mb)] initially decreased with no differences (P ≥ 0.296) between conditions and returned towards baseline by the completion of the test while Δ[deoxy(Hb + Mb)] increased with no differences between conditions and remained elevated until completion of the test (P ≥ 0.755). CONCLUSIONS: We verified the successful application of IPC via blood flow and NIRS measures but found no effects on performance of a 3 min maximal effort arm cranking test in young women.


Assuntos
Braço , Teste de Esforço/métodos , Precondicionamento Isquêmico , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Exercício Físico , Feminino , Humanos , Adulto Jovem
3.
J Strength Cond Res ; 33(6): 1640-1647, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28777244

RESUMO

Salom Huffman, L, Wadsworth, DD, McDonald, JR, Foote, SJ, Hyatt, H, and Pascoe, DD. Effects of a sprint interval and resistance concurrent exercise training program on aerobic capacity of inactive adult women. J Strength Cond Res 33(6): 1641-1648, 2019-The purpose of this investigation was to examine the effects of high-intensity concurrent exercise training (CET) consisting of sprint intervals (sprint interval training [SIT]) and resistance exercise (RET) protocols on aerobic capacity in recreationally active, adult women. A total of 53 participants were pair-matched according to preliminary maximal aerobic capacity (VO2max) Bruce protocol assessment into level-grade (SIT0) or 6% incline (SIT6) groups. This 12-week intervention consisted of 3 CET sessions per week. Sprint interval protocol consisted of 2 (weeks 1-6) then 3 (weeks 7-12) sets of three 40-second sprints at specific intensities to evoke responses equivalent to 95% of age-predicted maximal heart rate interspersed with 20 seconds of rest; with 1 minute of passive recovery between sets. An undulating periodization model consisting of lifts such as the back squat and bench press constituted the RET component. Protocol order alternated each session. Posttraining revealed significant improvements in both SIT0 and SIT6 (p ≤ 0.05) for VO2max (2.11 ± 0.390 to 2.29 ± 0.382 L·min; 2.03 ± 0.382 to 2.09 ± 0.561 L·min), Tmax (490.5 ± 102.3 to 542.7 ± 81.5 seconds; 503.2 ± 75.4 to 541.8 ± 77.0 seconds), and Vmax (5.1 ± 0.92 miles per hour [MPH] to 5.9 ± 0.90 MPH; 4.3 ± 0.68 MPH to 4.9 ± 0.64 MPH), respectively. No significant between-group interactions were detected for any of the variables. Our SIT-based CET intervention represents an effective strategy to induce significant cardiovascular adaptations in older women as evident by aerobic capacity improvements, beneficial to overall health and critical for functionality into old age; an important concern for aging women.


Assuntos
Adaptação Fisiológica , Tolerância ao Exercício/fisiologia , Treinamento Intervalado de Alta Intensidade , Consumo de Oxigênio , Treinamento Resistido , Teste de Esforço , Feminino , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Pessoa de Meia-Idade , Distribuição Aleatória
4.
Amino Acids ; 50(10): 1495, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30099596

RESUMO

For the author R. Mac Thompson, the first name should be R. Mac and the last name should be Thompson. On SpringerLink the name is listed correctly, but on PubMed he is listed as Mac Thompson R.

5.
Eur J Appl Physiol ; 118(11): 2465-2476, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30155761

RESUMO

PURPOSE: Betalains are indole-derived pigments found in beet root, and recent studies suggest that they may exert ergogenic effects. Herein, we examined if supplementation for 7 days with betalain-rich beetroot concentrate (BLN) improved cycling performance or altered hemodynamic and serum analytes prior to, during and following a cycling time trial (TT). METHODS: Twenty-eight trained male cyclists (29 ± 10 years, 77.3 ± 13.3 kg, and 3.03 ± 0.62 W/kg) performed a counterbalanced crossover study whereby BLN (100 mg/day) or placebo (PLA) supplementation occurred over 7 days with a 1-week washout between conditions. On the morning of day seven of each supplementation condition, participants consumed one final serving of BLN or PLA and performed a 30-min cycling TT with concurrent assessment of several physiological variables and blood markers. RESULTS: BLN supplementation improved average absolute power compared to PLA (231.6 ± 36.2 vs. 225.3 ± 35.8 W, p = 0.050, d = 0.02). Average relative power, distance traveled, blood parameters (e.g., pH, lactate, glucose, NOx) and inflammatory markers (e.g., IL-6, IL-8, IL-10, TNFα) were not significantly different between conditions. BLN supplementation significantly improved exercise efficiency (W/ml/kg/min) in the last 5 min of the TT compared to PLA (p = 0.029, d = 0.45). Brachial artery blood flow in the BLN condition, immediately post-exercise, tended to be greater compared to PLA (p = 0.065, d = 0.32). CONCLUSIONS: We report that 7 days of BLN supplementation modestly improves 30-min TT power output, exercise efficiency as well as post-exercise blood flow without increasing plasma NOx levels or altering blood markers of inflammation, oxidative stress, and/or hematopoiesis.


Assuntos
Desempenho Atlético/fisiologia , Betalaínas/administração & dosagem , Ciclismo/fisiologia , Suplementos Nutricionais , Consumo de Oxigênio/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Adulto , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Adulto Jovem
6.
Eur J Appl Physiol ; 117(12): 2587-2600, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29075862

RESUMO

PURPOSE: To compare the effects of external pneumatic compression (EPC) and sham when used concurrently with high intensity interval training (HIIT) on performance-related outcomes and recovery-related molecular measures. METHODS: Eighteen recreationally endurance-trained male participants (age: 21.6 ± 2.4 years, BMI: 25.7 ± 0.5 kg/m2, VO2peak: 51.3 ± 0.9 mL/kg/min) were randomized to balanced sham and EPC treatment groups. Three consecutive days of HIIT followed by EPC/sham treatment (Days 2-4) and 3 consecutive days of recovery (Days 5-7) with EPC/sham only on Days 5-6 were employed. Venipuncture, flexibility and pressure-to-pain threshold (PPT) measurements were made throughout. Vastus lateralis muscle was biopsied at PRE (i.e., Day 1), 1-h post-EPC/sham treatment on Day 2 (POST1), and 24-h post-EPC/sham treatment on Day 7 (POST2). 6-km run time trial performance was tested at PRE and POST2. RESULTS: No group × time interaction was observed for flexibility, PPT, or serum measures of creatine kinase (CK), hsCRP, and 8-isoprostane. However, there was a main effect of time for serum CK (p = 0.005). Change from PRE in 6-km run times at POST2 were not significantly different between groups. Significant between-groups differences existed for change from PRE in atrogin-1 mRNA (p = 0.018) at the POST1 time point (EPC: - 19.7 ± 8.1%, sham: + 7.7 ± 5.9%) and atrogin-1 protein concentration (p = 0.013) at the POST2 time point (EPC: - 31.8 ± 7.5%, sham: + 96.0 ± 34.7%). In addition, change from PRE in poly-Ub proteins was significantly different between groups at both the POST1 (EPC: - 26.0 ± 10.3%, sham: + 34.8 ± 28.5%; p = 0.046) and POST2 (EPC: - 33.7 ± 17.2%, sham: + 21.4 ± 14.9%; p = 0.037) time points. CONCLUSIONS: EPC when used concurrently with HIIT and in subsequent recovery days reduces skeletal muscle markers of proteolysis.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Dispositivos de Compressão Pneumática Intermitente/efeitos adversos , Proteólise , Adulto , Proteína C-Reativa/metabolismo , Creatina Quinase/sangue , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Masculino , Proteínas Musculares/metabolismo , Músculo Quadríceps/irrigação sanguínea , Músculo Quadríceps/metabolismo , Músculo Quadríceps/fisiologia , Proteínas Ligases SKP Culina F-Box/metabolismo , Ubiquitinação
7.
J Therm Biol ; 69: 155-162, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29037377

RESUMO

The importance of using infrared thermography (IRT) to assess skin temperature (tsk) is increasing in clinical settings. Recently, its use has been increasing in sports and exercise medicine; however, no consensus guideline exists to address the methods for collecting data in such situations. The aim of this study was to develop a checklist for the collection of tsk using IRT in sports and exercise medicine. We carried out a Delphi study to set a checklist based on consensus agreement from leading experts in the field. Panelists (n = 24) representing the areas of sport science (n = 8; 33%), physiology (n = 7; 29%), physiotherapy (n = 3; 13%) and medicine (n = 6; 25%), from 13 different countries completed the Delphi process. An initial list of 16 points was proposed which was rated and commented on by panelists in three rounds of anonymous surveys following a standard Delphi procedure. The panel reached consensus on 15 items which encompassed the participants' demographic information, camera/room or environment setup and recording/analysis of tsk using IRT. The results of the Delphi produced the checklist entitled "Thermographic Imaging in Sports and Exercise Medicine (TISEM)" which is a proposal to standardize the collection and analysis of tsk data using IRT. It is intended that the TISEM can also be applied to evaluate bias in thermographic studies and to guide practitioners in the use of this technique.


Assuntos
Temperatura Cutânea , Termografia/métodos , Animais , Regulação da Temperatura Corporal , Técnica Delphi , Exercício Físico , Terapia por Exercício/métodos , Humanos , Medicina Esportiva/métodos
8.
Amino Acids ; 48(3): 733-750, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26507545

RESUMO

We compared immediate post-exercise whey protein (WP, 500 mg) versus L-leucine (LEU, 54 mg) feedings on skeletal muscle protein synthesis (MPS) mechanisms and ribosome biogenesis markers 3 h following unilateral plantarflexor resistance exercise in male, Wistar rats (~250 g). Additionally, in vitro experiments were performed on differentiated C2C12 myotubes to compare nutrient (i.e., WP, LEU) and 'exercise-like' treatments (i.e., caffeine, hydrogen peroxide, and AICAR) on ribosome biogenesis markers. LEU and WP significantly increased phosphorylated-rpS6 (Ser235/236) in the exercised (EX) leg 2.4-fold (P < 0.01) and 2.7-fold (P < 0.001) compared to the non-EX leg, respectively, whereas vehicle-fed control (CTL) did not (+65 %, P > 0.05). Compared to the non-EX leg, MPS levels increased 32 % and 52 % in the EX leg of CTL (P < 0.01) and WP rats (P < 0.001), respectively, but not in LEU rats (+15 %, P > 0.05). Several genes associated with ribosome biogenesis robustly increased in the EX versus non-EX legs of all treatments; specifically, c-Myc mRNA, Nop56 mRNA, Bop1 mRNA, Ncl mRNA, Npm1 mRNA, Fb1 mRNA, and Xpo-5 mRNA. However, only LEU significantly increased 45S pre-rRNA levels in the EX leg (63 %, P < 0.001). In vitro findings confirmed that 'exercise-like' treatments similarly altered markers of ribosome biogenesis, but only LEU increased 47S pre-rRNA levels (P < 0.01). Collectively, our data suggests that resistance exercise, as well as 'exercise-like' signals in vitro, acutely increase the expression of genes associated with ribosome biogenesis independent of nutrient provision. Moreover, while EX with or without WP appears superior for enhancing translational efficiency (i.e., increasing MPS per unit of RNA), LEU administration (or co-administration) may further enhance ribosome biogenesis over prolonged periods with resistance exercise.


Assuntos
Leucina/metabolismo , Músculo Esquelético/metabolismo , Biossíntese de Proteínas , Treinamento Resistido , Ribossomos/metabolismo , Proteínas do Soro do Leite/metabolismo , Animais , Humanos , Masculino , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Nucleofosmina , Ratos , Ratos Wistar , Proteína S6 Ribossômica/genética , Proteína S6 Ribossômica/metabolismo , Ribossomos/genética
9.
Amino Acids ; 48(3): 779-789, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26553453

RESUMO

We examined if supplementing trained cyclists (32 ± 2 year, 77.8 ± 2.6 kg, and 7.4 ± 1.2 year training) with 12 g/day (6 g/day L-Leucine, 2 g/day L-Isoleucine and 4 g/day L-Valine) of either branched-chain amino acids (BCAAs, n = 9) or a maltodextrin placebo (PLA, n = 9) over a 10-week training season affected select body composition, performance, and/or immune variables. Before and after the 10-week study, the following was assessed: (1) 4-h fasting blood draws; (2) dual X-ray absorptiometry body composition; (3) Wingate peak power tests; and (4) 4 km time-trials. No group × time interactions existed for total lean mass (P = 0.27) or dual-leg lean mass (P = 0.96). A significant interaction existed for body mass-normalized relative peak power (19 % increase in the BCAA group pre- to post-study, P = 0.01), and relative mean power (4 % increase in the BCAA group pre- to post-study, P = 0.01). 4 km time-trial time to completion approached a significant interaction (P = 0.08), as the BCAA group improved in this measure by 11 % pre- to post-study, though this was not significant (P = 0.15). There was a tendency for the BCAA group to present a greater post-study serum BCAA: L-Tryptophan ratio compared to the PLA group (P = 0.08). A significant interaction for neutrophil number existed (P = 0.04), as there was a significant 18 % increase within the PLA group from the pre- to post-study time point (P = 0.01). Chronic BCAA supplementation improves sprint performance variables in endurance cyclists. Additionally, given that BCAA supplementation blunted the neutrophil response to intense cycling training, BCAAs may benefit immune function during a prolonged cycling season.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Atletas , Suplementos Nutricionais/análise , Neutrófilos/imunologia , Resistência Física , Adulto , Composição Corporal , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Adulto Jovem
10.
Eur J Appl Physiol ; 116(3): 601-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26721463

RESUMO

PURPOSE: The goal of this study was to compare the effect of work- and duration-matched interval training (HIIT) versus moderate aerobic endurance training (ET) on acute and chronic inflammation, along with changes in the lipid profile, to determine which may be more beneficial for improving cardiovascular health. METHODS: Twelve sedentary males (maximal oxygen consumption = 41.6 ± 5.4 mL kg(-1) min(-1)) completed 8 weeks of aerobic interval training or moderate aerobic training, with variables including C-reactive protein (CRP) for chronic inflammation, interleukin-6 (IL-6) response for the acute inflammatory response, plasma concentrations of high-density lipoprotein (HDL), total cholesterol (TC), triglycerides (TRG), and low-density lipoprotein, and body composition measured before and after the training period. RESULTS: HIIT decreased plasma TRG from 92 ± 32 to 61 ± 12 mg dL(-1), which was significantly different from ET, while ET improved the TC:HDL ratio from 4.67 ± 0.85 to 4.07 ± 0.96 and reduced the percentage of android fat from 36.78 ± 9.60 to 34.18 ± 11.39 %. Neither training protocol resulted in an acute IL-6 response on the first nor the last day of exercise, a change in chronic levels of CRP, or a significant increase in HDL, despite previous research finding these changes. CONCLUSIONS: It seems that in order to maximize the health outcomes from physical activity, both HIIT and ET should be included. The acute inflammatory response and reductions in chronic inflammation resulting from exercise training may not be as common as the literature suggests.


Assuntos
Composição Corporal , Proteína C-Reativa/metabolismo , Colesterol/sangue , Exercício Físico , Interleucina-6/sangue , Lipoproteínas HDL/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Triglicerídeos/sangue , Adulto Jovem
11.
Eur J Appl Physiol ; 116(11-12): 2267-2279, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27695978

RESUMO

INTRODUCTION: Inorganic nitrate ingestion has been posited to affect arterial blood pressure and vascular function. PURPOSE: We sought to determine the acute effect of a red spinach extract (RSE) high in inorganic nitrate on vascular reactivity 1-h after ingestion in peripheral conduit and resistance arteries. METHODS: Fifteen (n = 15; males 8, females 7) apparently healthy subjects (aged 23.1 ± 3.3 years; BMI 27.2 ± 3.7 kg/m2) participated in this crossover design, double-blinded study. Subjects reported to the lab ≥2-h post-prandial and consumed RSE (1000 mg dose; ~90 mg nitrate) or placebo (PBO). Venipuncture was performed on three occasions: baseline, 30-min post-ingestion and between 65 to 75-min post-ingestion. Baseline vascular measurements [i.e., calf venous occlusion plethysmography, brachial artery flow-mediated dilation (FMD)], 30-min of continuous blood pressure (BP) and heart rate (HR) analysis, and follow-up vascular measurements beginning at 40-min post-ingestion were also performed. RESULTS: Humoral nitrate following RSE ingestion was significantly higher at 30- (+54 %; P = 0.039) and 65 to 75-min post-ingestion compared to baseline (+255 %, P < 0.001) and PBO at the same time points (P < 0.05). No significant changes in BP or HR occurred in either condition. Peak reactive hyperemia (RH) calf blood flow increased significantly (+13.7 %; P = 0.016) following RSE ingestion, whereas it decreased (-14.0 %; P = 0.008) following PBO ingestion. No significant differential FMD responses were detected (P > 0.05), though RH was decreased following the baseline measure in both conditions. CONCLUSIONS: RSE significantly increased plasma nitrate 30-min post-ingestion, but acute microvascular (i.e., resistance vasculature) reactivity increases were isolated to the lower limb and no appreciable change in brachial artery FMD was observed.


Assuntos
Pressão Sanguínea/fisiologia , Artéria Braquial/efeitos dos fármacos , Nitratos/administração & dosagem , Spinacia oleracea/química , Resistência Vascular/fisiologia , Vasodilatação/fisiologia , Administração Oral , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Artéria Braquial/fisiologia , Feminino , Humanos , Masculino , Nitratos/sangue , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Resistência Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto Jovem
12.
J Strength Cond Res ; 30(11): 3057-3065, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26950345

RESUMO

Laird IV, RH, Elmer, DJ, Barberio, MD, Salom, LP, Lee, KA, and Pascoe, DD. Evaluation of performance improvements after either resistance training or sprint interval-based concurrent training. J Strength Cond Res 30(11): 3057-3065, 2016-The purpose of this investigation was to examine the effects of concurrent sprint interval and resistance training (CST) vs. resistance training (RT) on measures of strength, power, and aerobic fitness in recreationally active women. Twenty-eight women (20.3 ± 1.7 years; 63.0 ± 9.1; 51.1 ± 7.1 1 repetition maximum (1-RM) back squat (kg); V[Combining Dot Above]O2max: 35.4 ± 4.1 ml·kg·min) were recruited to complete an 11-week training program. Participants were matched-pair assigned to CST or RT cohorts after preliminary testing, which consisted of 1-RM back squats, maximal isometric squats, anaerobic power evaluations, and maximal oxygen consumption. All subjects trained 3 days per week with sprint-interval training occurring at least 4 hours after RT in the CST cohort. Both CST and RT resulted in significant improvements (p ≤ 0.05) in the 1-RM back squat (37.5 ± 7.8; 40.0 ± 9.6 kg), maximal isometric force (55.7 ± 51.3; 53.7 ± 36.7 kg), average peak anaerobic power testing (7.4 ± 6.2; 7.6 ± 6.4%), and zero-incline treadmill velocity, resulting in maximal oxygen consumption (1.8 ± 0.6; 0.8 ± 0.6 km·h). Only zero-incline treadmill velocity demonstrated a group-by-time interaction with a greater improvement after CST (p < 0.01). Rate of force development was not altered in either group. Results provide no evidence of interference to the adaptive process by CST. Coaches desiring improvements in strength, power, and endurance may want to evaluate how spring and high-intensity interval training might supplement programs already in place.


Assuntos
Desempenho Atlético/fisiologia , Treinamento Intervalado de Alta Intensidade , Treinamento Resistido , Teste de Esforço , Feminino , Humanos , Força Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Adulto Jovem
13.
Exp Physiol ; 100(7): 852-64, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25982469

RESUMO

NEW FINDINGS: What is the central question of this study? Does 60 min of peristaltic pulse external pneumatic compression (EPC) alter gene and protein expression patterns related to metabolism, vascular biology, redox balance and inflammation in vastus lateralis biopsy samples? What is the main finding and its importance? A single bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating endothelial nitric oxide synthase protein and nitric oxide metabolite concentrations in vastus lateralis biopsy samples. We investigated whether a single 60 min bout of whole-leg, lower pressure external pneumatic compression (EPC) altered select vascular, metabolic, antioxidant and inflammation-related mRNAs. Ten participants (eight male, two female; aged 22.0 ± 0.4 years) reported to the laboratory 4 h postprandial, and vastus lateralis muscle biopsies were obtained before (PRE) and 1 and 4 h after EPC treatment. Messenger RNA expression was analysed using real-time RT-PCR, and significant mRNA findings were investigated further by Western blot analysis of respective protein concentrations. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA increased by 77% 1 h following EPC compared with PRE levels (P = 0.005), but no change in protein concentration 1 or 4 h post-EPC was observed. Increases in endothelial nitric oxide sythase (eNOS) mRNA (+44%) and superoxide dismutase 2 (SOD2) mRNA (+57%) 1 h post-EPC as well as an increase in interleukin-10 mRNA (+132%) 4 h post-EPC compared with PRE levels were observed, but only approached significance (P = 0.076, 0.077 and 0.074, respectively). Interestingly, eNOS protein (+40%, P = 0.025) and nitrate and nitrite (NOx) concentrations (+69%, P = 0.025) increased 1-4 h post-EPC. Moreover, SOD2 protein tended to increase from PRE to 4 h post-EPC (+43%, P = 0.074), although no changes in tissue 4-hydroxnonenal levels was observed. An acute bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating eNOS protein and NOx concentrations in vastus lateralis biopsy samples. Future research should characterize the origin of these responses (e.g. vascular or muscle fibre cells) and how the acute effects of EPC application on gene and protein expression observed herein are associated with functional improvements (e.g. metabolism, vascular function) in acute and chronic models.


Assuntos
Perna (Membro)/fisiologia , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase Tipo III/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Feminino , Humanos , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fatores de Transcrição/metabolismo , Ativação Transcricional/fisiologia , Regulação para Cima , Adulto Jovem
14.
Chemistry ; 20(46): 15226-32, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25263341

RESUMO

The use of flow photochemistry and its apparent superiority over batch has been reported by a number of groups in recent years. To rigorously determine whether flow does indeed have an advantage over batch, a broad range of synthetic photochemical transformations were optimized in both reactor modes and their yields and productivities compared. Surprisingly, yields were essentially identical in all comparative cases. Even more revealing was the observation that the productivity of flow reactors varied very little to that of their batch counterparts when the key reaction parameters were matched. Those with a single layer of fluorinated ethylene propylene (FEP) had an average productivity 20% lower than that of batch, whereas three-layer reactors were 20% more productive. Finally, the utility of flow chemistry was demonstrated in the scale-up of the ring-opening reaction of a potentially explosive [1.1.1] propellane with butane-2,3-dione.


Assuntos
Reação de Cicloadição/instrumentação , Fotoquímica/instrumentação , Reação de Cicloadição/economia , Desenho de Equipamento , Processos Fotoquímicos , Fotoquímica/economia , Politetrafluoretileno/análogos & derivados , Politetrafluoretileno/química , Raios Ultravioleta
15.
Org Lett ; 26(14): 2857-2861, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38198695

RESUMO

The C-aryl-tetrahydropyran motif is prevalent in nature in a number of natural products with biological activity; however, this challenging architecture still requires novel synthetic approaches. We demonstrate the application of a stereoselective Heck redox-relay strategy for the synthesis of functionalized 2,6-trans-tetrahydropyrans in excellent selectivity in a single step from an enantiopure dihydropyranyl alcohol, proceeding through a novel exo-cyclic migration. The strategy has also been applied to the total synthesis of a trans-epimer of the natural product centrolobine in excellent yield and stereoselectivity.

16.
J Med Chem ; 67(12): 10464-10489, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38866424

RESUMO

The bromodomain and extra terminal (BET) family of bromodomain-containing proteins are important epigenetic regulators that elicit their effect through binding histone tail N-acetyl lysine (KAc) post-translational modifications. Recognition of such markers has been implicated in a range of oncology and immune diseases and, as such, small-molecule inhibition of the BET family bromodomain-KAc protein-protein interaction has received significant interest as a therapeutic strategy, with several potential medicines under clinical evaluation. This work describes the structure- and property-based optimization of a ligand and lipophilic efficient pan-BET bromodomain inhibitor series to deliver candidate I-BET787 (70) that demonstrates efficacy in a mouse model of inflammation and suitable properties for both oral and intravenous (IV) administration. This focused two-phase explore-exploit medicinal chemistry effort delivered the candidate molecule in 3 months with less than 100 final compounds synthesized.


Assuntos
Administração Intravenosa , Animais , Administração Oral , Camundongos , Relação Estrutura-Atividade , Humanos , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Estrutura Molecular
17.
Angew Chem Int Ed Engl ; 52(49): 13076-9, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24155206

RESUMO

Changing course: While organolithium and Grignard reagents favor addition to C1 of A (R=Me), the corresponding organoytterbium reagents add to C2 (R=tBu). Computational studies provide insights into the nature of organoytterbium species and their reactivity, and a total synthesis of (-)-mansonone B illustrates the utility of the method in terpenoid synthesis. Tf=trifluoromethanesulfonyl.


Assuntos
Butadienos/química , Ciclobutanos/química , Hemiterpenos/química , Hidroquinonas/síntese química , Compostos Organometálicos/química , Pentanos/química , Itérbio/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Ciclobutanos/síntese química , Hidroquinonas/química , Cetonas/síntese química , Cetonas/química , Modelos Moleculares , Estrutura Molecular
18.
J Funct Morphol Kinesiol ; 7(4)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36547656

RESUMO

The purpose of this project was to examine the effect of a concurrent exercise program (sprint interval training and resistance exercise) on body composition in women with obesity and factors associated with continued exercise participation following the program. Twenty women (37.1 ± 7.4 y, height = 1.63 ± 0.09 m, weight = 98.22 ± 0.22 kg, BMI = 34.2 ± 2.50 kg/m2) participated in a 10-week exercise intervention consisting of a sprint interval treadmill protocol and resistance training three times a week totaling 30 sessions. Body composition was measured by dual-energy X-ray absorptiometry (iDXA) at pretest, 12 weeks, and six months post-intervention. Semi-structured interviews assessed participants' perception of the program at both 12 weeks and six months. Participants significantly reduced fat mass (p < 0.001), gynoid fat mass (p < 0.010), android fat mass (p = 0.003), and visceral fat mass (p = 0.003) at 12 weeks post-test. At six months, participants maintained their reductions in fat mass (p = 0.015), visceral fat (p = 0.040) and gynoid fat mass (p = 0.032). There were no significant main time effects in lean mass (p = 0.099) or caloric intake (p = 0.053) at 12 weeks or six months. Themes that emerged from the semi-structured interviews at 12 weeks reflected enjoyment in the training, increases in competence and knowledge, as well as apprehension of continuing training on their own. At six months, themes that emerged reflected overcoming barriers, competence regarding high-intensity training, and a lack of competence to engage in resistance training. Sprint interval training coupled with resistance training is a feasible exercise protocol for women with obesity and results in reduced fat mass over six months. Improving women's competence for training is imperative for continued participation.

19.
J Strength Cond Res ; 25(12): 3501-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22076092

RESUMO

Strecker, E, Foster, EB, and Pascoe, DD. Test-retest reliability for hitting accuracy tennis test. J Strength Cond Res 25(12): 3501-3505, 2011-The purpose of this investigation was to assess a test-retest reliability of the hitting accuracy tennis test (HATT). Twelve National Collegiate Athletic Association (NCAA) division I tennis players (4 men and 8 women) volunteered to participate in this investigation. Skill tests consisted of 15 consecutive ground strokes in all 4 directions (forehand [FH] and backhand [BH]; crosscourt and up the line) with not >1 minute between directions. The court was divided into 12 areas, and each area was assigned a value according to a grid system based on offensive, defensive, and neutral shots ranging from 1 point to 6 points. Total score, unforced errors, and shot index (total number of shots that landed on optimal performance areas 5 and 6 minus total number of unforced errors) were used for statistical analysis. The order of shot direction was randomized between participants and trials. The analysis of variance with repeated measures (p value ≤ 0.05) of this investigation showed no statistical difference between trials on any of the measurements. The results also suggest that division I level tennis players have the ability to hit accurately specific targets on a tennis court using either FH or BH with minimal daily variation. Therefore, we conclude that the HATT for trained tennis athletes is a simple, reliable, and accurate assessment tool to measure tennis skill performance based on accuracy. The HATT is also an easy, inexpensive training device that coaches can use to monitor players development.


Assuntos
Destreza Motora/fisiologia , Tênis/fisiologia , Adolescente , Adulto , Análise de Variância , Desempenho Atlético , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Análise e Desempenho de Tarefas , Adulto Jovem
20.
J Athl Train ; 55(1): 71-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31876454

RESUMO

CONTEXT: Slips, trips, and falls are leading causes of musculoskeletal injuries in firefighters. Researchers have hypothesized that heat stress is the major contributing factor to these fireground injuries. OBJECTIVE: To examine the effect of environmental conditions, including hot and ambient temperatures, and exercise on functional and physiological outcome measures, including balance, rectal temperature, and perceived exertion. DESIGN: Randomized controlled clinical trial. SETTING: Laboratory environmental chamber. PATIENTS OR OTHER PARTICIPANTS: A total of 13 healthy, active career firefighters (age = 26 ± 6 years [range = 19-35 years], height = 178.61 ± 4.93 cm, mass = 86.56 ± 16.13 kg). INTERVENTION(S): Independent variables consisted of 3 conditions (exercise in heat [37.41°C], standing in heat [37.56°C], and exercise in ambient temperature [14.24°C]) and 3 data-collection times (preintervention, postintervention, and postrecovery). Each condition was separated from the others by at least 1 week and lasted a maximum of 40 minutes or until the participant reached volitional fatigue or a rectal temperature of 40.0°C. MAIN OUTCOME MEASURE(S): Firefighting-specific functional balance performance index, rectal temperature, and rating of perceived exertion. RESULTS: Exercise in the heat decreased functional balance, increased rectal temperature, and altered the perception of exertion compared with the other intervention conditions. CONCLUSIONS: A bout of exercise in a hot, humid environment increased rectal temperature in a similar way to that reported in the physically active population and negatively affected measures of functional balance. Rather than independently affecting balance, the factors of exercise and heat stress appeared to combine, leading to an increased likelihood of slips, trips, and falls.


Assuntos
Exposição Ambiental , Bombeiros/estatística & dados numéricos , Transtornos de Estresse por Calor/fisiopatologia , Temperatura Alta/efeitos adversos , Traumatismos Ocupacionais , Esforço Físico/fisiologia , Equilíbrio Postural/fisiologia , Adulto , Temperatura Corporal/fisiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Exercício Físico/fisiologia , Humanos , Masculino , Traumatismos Ocupacionais/classificação , Traumatismos Ocupacionais/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde , Desempenho Físico Funcional
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