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1.
J Surg Case Rep ; 2024(4): rjae221, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38605693

RESUMEN

Profunda femoris artery aneurysms are a rare form of peripheral arterial aneurysm. In this report, we present the case of an 83-year-old lady who was found to have a 65 mm aneurysm arising from the proximal left profunda femoris artery and associated pseudoaneurysm. Successful treatment was achieved using an endovascular approach in which two stents were deployed.

2.
Nutrients ; 15(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38004115

RESUMEN

This research aimed to determine the effects of Gynostemma pentaphyllum (G. pentaphyllum) on exercise performance, AMP-activated protein kinase (AMPK), and mitochondrial signaling in human muscle. This randomized double-blind placebo control crossover study provided placebo or 450 mg of G. pentaphyllum dried leaf extract equivalent to 2.25 g of dry leaf per day for four weeks to 16 healthy untrained young males, separated by four weeks wash-out. Following 4-week supplementation with G. pentaphyllum, participants had significantly lower leptin and blood glucose levels and improved time trial performance over 20 km, which corresponded with a higher muscle oxygen flux compared to placebo. Muscle AMPK Thr172 phosphorylation significantly increased after 60 min exercise following G. pentaphyllum supplementation. AMPK Thr172 phosphorylation levels relative to total AMPK increased earlier following exercise with G. pentaphyllum compared to placebo. Total ACC-α was lower following G. pentaphyllum supplementation compared to placebo. While further research is warranted, G. pentaphyllum supplementation improved exercise performance in healthy untrained males, which corresponded with improved mitochondrial respiration, altered AMPK and ACC, and decreased plasma leptin and glucose levels.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Leptina , Humanos , Masculino , Proteínas Quinasas Activadas por AMP/metabolismo , Estudios Cruzados , Gynostemma , Extractos Vegetales/farmacología
3.
JBMR Plus ; 6(11): e10667, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36398112

RESUMEN

Osteoglycin (OGN) is a leucine-rich proteoglycan that has been implicated in the regulation of glucose in animal models. However, its relationship with glucose control in humans is unclear. We examined the effect of high-intensity interval exercise (HIIE) and hyperinsulinemic-euglycemic clamp on circulating levels of OGN as well as whether circulating OGN levels are associated with markers of glycemic control and cardio-metabolic health. Serum was analyzed for OGN (ELISA) levels from 9 middle-aged obese men (58.1 ± 2.2 years, body mass index [BMI] = 33.1 ± 1.4 kg∙m-2, mean ± SEM) and 9 young men (27.8 ± 1.6 years, BMI = 24.4 ± 0.08 kg∙m-2) who previously completed a study involving a euglycemic-hyperinsulinemic clamp at rest and after HIIE (4x4 minutes cycling at approximately 95% peak heart rate (HRpeak), interspersed with 2 minutes of active recovery). Blood pressure, body composition (dual-energy X-ray absorptiometry), and insulin sensitivity (hyperinsulinemic-euglycemic clamp) were assessed. Serum OGN was higher in the young cohort compared with the middle-aged cohort (65.2 ± 10.1 ng/mL versus 36.5 ± 4. 5 ng/mL, p ≤ 0.05). Serum OGN was unaffected by acute HIIE but decreased after the insulin clamp compared with baseline (~-27%, p = 0.01), post-exercise (~-35%, p = 0.01), and pre-clamp (~-32%, p = 0.02) time points, irrespective of age. At baseline, lower circulating OGN levels were associated with increased age, BMI, and fat mass, whereas higher OGN levels were related to lower fasting glucose. Higher OGN levels were associated with a higher glucose infusion rate. Exercise had a limited effect on circulating OGN. The mechanisms by which OGN affects glucose regulation should be explored in the future. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

4.
Bone ; 165: 116545, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36108920

RESUMEN

Bone and muscle are closely linked mechanically and biochemically. Bone hormones secreted during bone remodeling might be linked to muscle mass and strength maintenance. Exercise elicits high mechanical strain and is essential for bone health. However, the relationship between commonly used bone turnover markers (BTMs) and muscle function in community dwelling older adults remains unclear. It is also unknown how acute exercise with differing mechanical strain may affect BTMs, and whether baseline muscle function alters BTM responses differently. We tested the hypothesis that BTMs are associated with muscle function, and that acute exercise could change the circulating levels of BTMs. Thirty-five older adults (25 females/10 males, 72.8 ± 6.0 years) participated. Baseline assessments included body composition (DXA), handgrip strength and a physical performance test (PPT) (gait speed, timed-up-and-go [TUG], stair ascent/descent). Leg muscle quality (LMQ) and stair climb power (SCP) were calculated. Participants performed (randomized) 30 min aerobic (AE) (cycling 70%HRPeak) and resistance (RE) (leg press 70%RM, jumping) exercise. Serum ß-isomerized C-terminal telopeptides (ß-CTX), procollagen of type I propeptide (P1NP), total osteocalcin (t)OC and ucOC were assessed at baseline and post-exercise. Data were analyzed using linear mixed models and simple regressions, adjusted for sex. At baseline, higher muscle strength (LMQ, handgrip) was related to higher P1NP, higher SCP was related to higher P1NP and ß-CTX, and better physical performance (lower PPT) related to higher P1NP and ß-CTX (p < 0.05). Exercise, regardless of mode, decreased ß-CTX and tOC (all p < 0.05), while P1NP and ucOC remained unaltered. Higher baseline handgrip strength, SCP and LMQ was associated with lower post-exercise ß-CTX responses, and poorer baseline mobility (increased TUG time) was associated with higher post-exercise ß-CTX. Independently of exercise mode, acute exercise decreased ß-CTX and tOC. Our data suggest that in older adults at baseline, increased BTM levels were linked to better muscle function. Altogether, our data strengthens the evidence for bone-muscle interaction, however, mechanisms behind this specific component of bone-muscle crostalk remain unclear.


Asunto(s)
Fuerza de la Mano , Procolágeno , Anciano , Femenino , Humanos , Masculino , Biomarcadores , Remodelación Ósea , Colágeno Tipo I , Ejercicio Físico , Hormonas , Músculos , Osteocalcina , Fragmentos de Péptidos
5.
Med Sci Sports Exerc ; 54(12): 2167-2177, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36136596

RESUMEN

INTRODUCTION: Female athletes sleep less and report more sleep problems than their male counterparts. Inadequate sleep reduces maximal strength in male athletes; however, little is known about the impact of sleep restriction (SR) on the quantity and quality of resistance exercise performed by female athletes. This study investigated the effect of nine nights of moderate SR on repeated resistance exercise performance, hormonal responses, and perceived fatigue in females. METHODS: Ten healthy, resistance-trained, eumenorrheic females age 18-35 yr underwent nine nights of SR (5-h time in bed) and normal sleep (NS; ≥7-h time in bed) in a randomized, crossover fashion with a minimum 6-wk washout. Participants completed four resistance exercise sessions per trial, with blood samples collected before and after exercise. Exercise performance was assessed using volume load, reactive strength index, and mean concentric velocity with rating of perceived exertion recorded after exercise. Participants completed awakening saliva sampling and the Multi-component Training Distress Scale daily. RESULTS: Volume load decreased trivially (<1%, P < 0.05) with SR. Mean concentric velocity per set was slower during SR for the lower-body (up to 15%, P < 0.05), but not the upper-body, compound lifts. Intraset velocity loss was up to 7% greater during SR for back squats ( P < 0.05). SR increased salivary cortisol area under the curve (by 42%), total training distress (by 84%), and session perceived exertion (by 11%). CONCLUSIONS: Sustained SR reduces markers of resistance exercise quality (bar velocity) more than quantity (volume load) and increases perceived effort at the same relative intensity in resistance-trained females. Markers of exercise quality and internal load may be more sensitive than volume load, to advise coaches to the decline in lifting performance for female athletes experiencing SR.


Asunto(s)
Entrenamiento de Fuerza , Adolescente , Adulto , Femenino , Humanos , Adulto Joven , Atletas , Ejercicio Físico/fisiología , Sueño/fisiología , Privación de Sueño
6.
Front Endocrinol (Lausanne) ; 13: 863224, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937838

RESUMEN

Background: Inadequate sleep is associated with many detrimental health effects, including increased risk of developing insulin resistance and type 2 diabetes. These effects have been associated with changes to the skeletal muscle transcriptome, although this has not been characterised in response to a period of sleep restriction. Exercise induces a beneficial transcriptional response within skeletal muscle that may counteract some of the negative effects associated with sleep restriction. We hypothesised that sleep restriction would down-regulate transcriptional pathways associated with glucose metabolism, but that performing exercise would mitigate these effects. Methods: 20 healthy young males were allocated to one of three experimental groups: a Normal Sleep (NS) group (8 h time in bed per night (TIB), for five nights (11 pm - 7 am)), a Sleep Restriction (SR) group (4 h TIB, for five nights (3 am - 7 am)), and a Sleep Restriction and Exercise group (SR+EX) (4 h TIB, for five nights (3 am - 7 am) and three high-intensity interval exercise (HIIE) sessions (performed at 10 am)). RNA sequencing was performed on muscle samples collected pre- and post-intervention. Our data was then compared to skeletal muscle transcriptomic data previously reported following sleep deprivation (24 h without sleep). Results: Gene set enrichment analysis (GSEA) indicated there was an increased enrichment of inflammatory and immune response related pathways in the SR group post-intervention. However, in the SR+EX group the direction of enrichment in these same pathways occurred in the opposite directions. Despite this, there were no significant changes at the individual gene level from pre- to post-intervention. A set of genes previously shown to be decreased with sleep deprivation was also decreased in the SR group, but increased in the SR+EX group. Conclusion: The alterations to inflammatory and immune related pathways in skeletal muscle, following five nights of sleep restriction, provide insight regarding the transcriptional changes that underpin the detrimental effects associated with sleep loss. Performing three sessions of HIIE during sleep restriction attenuated some of these transcriptional changes. Overall, the transcriptional alterations observed with a moderate period of sleep restriction were less evident than previously reported changes following a period of sleep deprivation.


Asunto(s)
Diabetes Mellitus Tipo 2 , Privación de Sueño , Humanos , Masculino , Músculo Esquelético/metabolismo , Sueño/fisiología , Privación de Sueño/genética , Privación de Sueño/metabolismo , Transcriptoma
7.
J Physiol ; 600(16): 3749-3774, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35837833

RESUMEN

We investigated whether digoxin lowered muscle Na+ ,K+ -ATPase (NKA), impaired muscle performance and exacerbated exercise K+ disturbances. Ten healthy adults ingested digoxin (0.25 mg; DIG) or placebo (CON) for 14 days and performed quadriceps strength and fatiguability, finger flexion (FF, 105%peak-workrate , 3 × 1 min, fourth bout to fatigue) and leg cycling (LC, 10 min at 33% V O 2 peak ${\rm{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ and 67% V O 2 peak ${\rm{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ , 90% V O 2 peak ${\rm{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ to fatigue) trials using a double-blind, crossover, randomised, counter-balanced design. Arterial (a) and antecubital venous (v) blood was sampled (FF, LC) and muscle biopsied (LC, rest, 67% V O 2 peak ${\rm{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ , fatigue, 3 h after exercise). In DIG, in resting muscle, [3 H]-ouabain binding site content (OB-Fab ) was unchanged; however, bound-digoxin removal with Digibind revealed total ouabain binding (OB+Fab ) increased (8.2%, P = 0.047), indicating 7.6% NKA-digoxin occupancy. Quadriceps muscle strength declined in DIG (-4.3%, P = 0.010) but fatiguability was unchanged. During LC, in DIG (main effects), time to fatigue and [K+ ]a were unchanged, whilst [K+ ]v was lower (P = 0.042) and [K+ ]a-v greater (P = 0.004) than in CON; with exercise (main effects), muscle OB-Fab was increased at 67% V O 2 peak ${\rm{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ (per wet-weight, P = 0.005; per protein P = 0.001) and at fatigue (per protein, P = 0.003), whilst [K+ ]a , [K+ ]v and [K+ ]a-v were each increased at fatigue (P = 0.001). During FF, in DIG (main effects), time to fatigue, [K+ ]a , [K+ ]v and [K+ ]a-v were unchanged; with exercise (main effects), plasma [K+ ]a , [K+ ]v , [K+ ]a-v and muscle K+ efflux were all increased at fatigue (P = 0.001). Thus, muscle strength declined, but functional muscle NKA content was preserved during DIG, despite elevated plasma digoxin and muscle NKA-digoxin occupancy, with K+ disturbances and fatiguability unchanged. KEY POINTS: The Na+ ,K+ -ATPase (NKA) is vital in regulating skeletal muscle extracellular potassium concentration ([K+ ]), excitability and plasma [K+ ] and thereby also in modulating fatigue during intense contractions. NKA is inhibited by digoxin, which in cardiac patients lowers muscle functional NKA content ([3 H]-ouabain binding) and exacerbates K+ disturbances during exercise. In healthy adults, we found that digoxin at clinical levels surprisingly did not reduce functional muscle NKA content, whilst digoxin removal by Digibind antibody revealed an ∼8% increased muscle total NKA content. Accordingly, digoxin did not exacerbate arterial plasma [K+ ] disturbances or worsen fatigue during intense exercise, although quadriceps muscle strength was reduced. Thus, digoxin treatment in healthy participants elevated serum digoxin, but muscle functional NKA content was preserved, whilst K+ disturbances and fatigue with intense exercise were unchanged. This resilience to digoxin NKA inhibition is consistent with the importance of NKA in preserving K+ regulation and muscle function.


Asunto(s)
Digoxina , Ouabaína , Adulto , Digoxina/metabolismo , Fatiga , Humanos , Músculo Esquelético/fisiología , Sodio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
8.
BMJ Open ; 12(5): e060869, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35545400

RESUMEN

INTRODUCTION: Gender affirming hormone therapy (GAHT) is increasingly used by transgender individuals and leads to shifts in sex hormone levels. Skeletal muscle is highly responsive to hormone activity, with limited data on the effects of GAHT on different human tissues. Here, we present the protocol for the GAME study (the effects of Gender Affirming hormone therapy on skeletal Muscle training and Epigenetics), which aims to uncover the effects of GAHT on skeletal muscle 'omic' profiles (methylomics, transcriptomics, proteomics, metabolomics) and markers of skeletal muscle health and fitness. METHODS AND ANALYSIS: This study is a prospective age-matched cohort study in transgender adults commencing GAHT (n=80) and age-matched individuals not commencing GAHT (n=80), conducted at Austin Health and Victoria University in Victoria, Australia. Assessments will take place prior to beginning GAHT and 6 and 12 months into therapies in adults commencing GAHT. Age-matched individuals will be assessed at the same time points. Assessments will be divided over three examination days, involving (1) aerobic fitness tests, (2) muscle strength assessments and (3) collection of blood and muscle samples, as well as body composition measurements. Standardised diets, fitness watches and questionnaires will be used to control for key confounders in analyses. Primary outcomes are changes in aerobic fitness and muscle strength, as well as changes in skeletal muscle DNA methylation and gene expression profiles. Secondary outcomes include changes in skeletal muscle characteristics, proteomics, body composition and blood markers. Linear mixed models will be used to assess changes in outcomes, while accounting for repeated measures within participants and adjusting for known confounders. ETHICS AND DISSEMINATION: The Austin Health Human Research Ethics Committee (HREC) and Victoria University HREC granted approval for this study (HREC/77146/Austin-2021). Findings from this project will be published in open-access, peer-reviewed journals and presented to scientific and public audiences. TRIAL REGISTRATION NUMBER: ACTRN12621001415897; Pre-results.


Asunto(s)
Personas Transgénero , Adulto , Estudios de Cohortes , Hormonas , Humanos , Músculo Esquelético , Estudios Prospectivos , Victoria
9.
Hum Reprod ; 37(5): 1018-1029, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35325125

RESUMEN

STUDY QUESTION: Does 12 weeks of high-intensity interval training (HIIT) result in greater improvements in cardio-metabolic and reproductive outcomes compared to standard moderate-intensity continuous training (MICT) in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: HIIT offers greater improvements in aerobic capacity, insulin sensitivity and menstrual cyclicity, and larger reductions in hyperandrogenism compared to MICT. WHAT IS KNOWN ALREADY: Exercise training is recognized to improve clinical outcomes in women with PCOS, but little is known about whether HIIT results in greater health outcomes compared to standard MICT. STUDY DESIGN, SIZE, DURATION: This was a two-armed randomized clinical trial enrolling a total of 29 overweight women with PCOS between May 2016 and November 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% peak heart rate, N = 14) or HIIT (>90% peak heart rate, N = 15), each completed three times per week. The primary clinical outcomes were aerobic capacity (VO2peak) and insulin sensitivity (euglycaemic-hyperinsulinaemic clamp). Secondary outcomes included hormonal profiles, menstrual cyclicity and body composition. MAIN RESULTS AND THE ROLE OF CHANCE: Both HIIT and MICT improved VO2peak (HIIT; Δ 5.8 ± 2.6 ml/kg/min, P < 0.001 and MICT; Δ 3.2 ± 2 ml/kg/min, P < 0.001), however, the HIIT group had a greater improvement in aerobic capacity compared to MICT (ß = 2.73 ml/kg/min, P = 0.015). HIIT increased the insulin sensitivity index compared to baseline (Δ 2.3 ± 4.4 AU, P = 0.007) and MICT (ß = 0.36 AU, P = 0.030), and caused higher increases in sex hormone-binding globulin compared to MICT (ß = 0.25 nmol/l, P = 0.002). HIIT participants were 7.8 times more likely to report improved menstrual cyclicity than those in the MICT group (odds ratio 7.8, P = 0.04). LIMITATIONS, REASONS FOR CAUTION: This study has a small sample size and the findings of the effect of the exercise interventions are limited to overweight reproductive-aged women, who do not have any co-existing co-morbidities that require medication. WIDER IMPLICATIONS OF THE FINDINGS: Exercise, regardless of intensity, has clear health benefits for women with PCOS. HIIT appears to be a more beneficial strategy and should be considered for promoting health and reducing cardio-metabolic risk in overweight women with PCOS. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a Project Support Grant from the Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence in PCOS. The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: ACTRN12615000242527. TRIAL REGISTRATION DATE: 19 February 2015. DATE OF FIRST PATIENT'S ENROLMENT: 27 May 2016.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Resistencia a la Insulina , Síndrome del Ovario Poliquístico , Adulto , Australia , Femenino , Entrenamiento de Intervalos de Alta Intensidad/métodos , Humanos , Sobrepeso/complicaciones , Sobrepeso/terapia , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/terapia
10.
Int J Mol Sci ; 23(5)2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35269762

RESUMEN

Autophagy is a key intracellular mechanism by which cells degrade old or dysfunctional proteins and organelles. In skeletal muscle, evidence suggests that exercise increases autophagosome content and autophagy flux. However, the exercise-induced response seems to differ between rodents and humans, and little is known about how different exercise prescription parameters may affect these results. The present study utilised skeletal muscle samples obtained from four different experimental studies using rats and humans. Here, we show that, following exercise, in the soleus muscle of Wistar rats, there is an increase in LC3B-I protein levels immediately after exercise (+109%), and a subsequent increase in LC3B-II protein levels 3 h into the recovery (+97%), despite no change in Map1lc3b mRNA levels. Conversely, in human skeletal muscle, there is an immediate exercise-induced decrease in LC3B-II protein levels (-24%), independent of whether exercise is performed below or above the maximal lactate steady state, which returns to baseline 3.5 h following recovery, while no change in LC3B-I protein levels or MAP1LC3B mRNA levels is observed. SQSTM1/p62 protein and mRNA levels did not change in either rats or humans following exercise. By employing an ex vivo autophagy flux assay previously used in rodents we demonstrate that the exercise-induced decrease in LC3B-II protein levels in humans does not reflect a decreased autophagy flux. Instead, effect size analyses suggest a modest-to-large increase in autophagy flux following exercise that lasts up to 24 h. Our findings suggest that exercise-induced changes in autophagosome content markers differ between rodents and humans, and that exercise-induced decreases in LC3B-II protein levels do not reflect autophagy flux level.


Asunto(s)
Autofagia , Condicionamiento Físico Animal , Animales , Autofagia/fisiología , Biomarcadores/metabolismo , Humanos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Músculo Esquelético/metabolismo , Condicionamiento Físico Animal/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar
11.
PeerJ ; 10: e12856, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35186464

RESUMEN

BACKGROUND: Exercise elicits a range of adaptive responses in skeletal muscle, which include changes in mRNA expression. To better understand the health benefits of exercise training, it is important to investigate the underlying molecular mechanisms of skeletal muscle adaptation to exercise. However, most studies have assessed the molecular events at only a few time-points within a short time frame post-exercise, and the variations of gene expression kinetics have not been addressed systematically. METHODS: We assessed the mRNA expression of 23 gene isoforms implicated in the adaptive response to exercise at six time-points (0, 3, 9, 24, 48, and 72 h post exercise) over a 3-day period following a single session of high-intensity interval exercise. RESULTS: The temporal patterns of target gene expression were highly variable and the expression of mRNA transcripts detected was largely dependent on the timing of muscle sampling. The largest fold change in mRNA expression of each tested target gene was observed between 3 and 72 h post-exercise. DISCUSSION AND CONCLUSIONS: Our findings highlight an important gap in knowledge regarding the molecular response to exercise, where the use of limited time-points within a short period post-exercise has led to an incomplete understanding of the molecular response to exercise. Muscle sampling timing for individual studies needs to be carefully chosen based on existing literature and preliminary analysis of the molecular targets of interest. We propose that a comprehensive time-course analysis on the exercise-induced transcriptional response in humans will significantly benefit the field of exercise molecular biology.


Asunto(s)
Ejercicio Físico , Músculo Esquelético , Humanos , Ejercicio Físico/fisiología , Músculo Esquelético/metabolismo , Cinética , Biopsia , ARN Mensajero/genética
12.
J Exerc Sci Fit ; 20(1): 70-76, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35024050

RESUMEN

The aim of this study was to compare high-intensity interval exercise (HIIE) sessions prescribed on the basis of a maximal value (peak power output, PPO) and a submaximal value (lactate threshold, LT) derived from graded exercise tests (GXTs) in normoxia and hypoxia. METHODS: A total of ten males (aged 18-37) volunteered to participate in this study. The experimental protocol consisted of a familiarization procedure, two GXTs under normoxia (FiO2 = 0.209) and two GXTs under normobaric hypoxia (FiO2 = 0.140), and three HIIE sessions performed in a random order. The HIIE sessions included one at hypoxia (HY) and two at normoxia (one matched for the absolute intensity in hypoxia, designated as NA, and one matched for the relative intensity in hypoxia, designated as NR). RESULTS: The data demonstrated that there was significant lower peak oxygen uptake (V̇O2peak), peak heart rate (HRpeak), PPO, and LT derived from GXTs in hypoxia, with higher respiratory exchange ratio (RER), when compared to those from GXTs performed in normoxia (p < 0.001). Among the three HIIE sessions, the NA session resulted in lower percentage of HRpeak (85.0 ± 7.5% vs 94.4 ± 5.0%; p = 0.002) and V̇O2peak (74.1 ± 9.1% vs 88.7 ± 7.7%; p = 0.005), when compared to the NR session. HIIE sessions in HY and NR resulted in similar percentage of HRpeak and V̇O2peak, as well as similar rating of perceived exertion and RER. The blood lactate level increased immediately after all the three HIIE sessions (p < 0.001), while higher blood lactate concentrations were observed immediately after the HY (p = 0.0003) and NR (p = 0.014) sessions when compared with NA. CONCLUSION: Combining of PPO and LT derived from GXTs can be used to prescribe exercise intensity of HIIE in hypoxia.

14.
Physiol Rep ; 9(15): e14962, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34327858

RESUMEN

AIM: Observed effects of exercise are highly variable between individuals, and subject-by-training interaction (i.e., individual response variability) is often not estimated. Here, we measured mitochondrial (citrate synthetase, cytochrome-c oxidase, succinate dehydrogenase, and mitochondrial copy-number), performance markers (Wpeak , lactate threshold [LT], and VO2peak ), and fiber type proportions/expression (type I, type IIa, and type IIx) in multiple time points during 12-week of high-intensity interval training (HIIT) to investigate effects of exercise at the individual level. METHODS: Sixteen young (age: 33.1 ± 9.0 years), healthy men (VO2peak 35-60 ml/min/kg and BMI: 26.4 ± 4.2) from the Gene SMART study completed 12-week of progressive HIIT. Performance markers and muscle biopsies were collected every 4 weeks. We used mixed-models and bivariate growth models to quantify individual response and to estimate correlations between variables. RESULTS: All performance markers exhibited significant (Wpeak 0.56 ± 0.33 p = 0.003, LT 0.37 ± 0.35 p = 0.007, VO2peak 3.81 ± 6.13 p = 0.02) increases overtime, with subject-by-training interaction being present (95% CI: Wpeak 0.09-0.24, LT 0.06-0.18, VO2peak 0.27-2.32). All other measurements did not exhibit significant changes. Fiber type IIa proportions at baseline was significantly associated with all physiological variables (p < 0.05), and citrate synthetase and cytochrome-c oxidase levels at baseline and overtime (i.e., intercept and slope) presented significant covariance (p < 0.05). Finally, low correlations between performance and mitochondrial markers were observed. CONCLUSION: We identified a significant subject-by-training interaction for the performance markers. While for all other measures within-subject variability was too large and interindividual differences in training efficacy could not be verified. Changes in measurements in response to exercise were not correlated, and such disconnection should be further investigated by future studies.


Asunto(s)
Adaptación Fisiológica , Biomarcadores/metabolismo , Capacidad Cardiovascular , Ejercicio Físico , Entrenamiento de Intervalos de Alta Intensidad , Mitocondrias/fisiología , Consumo de Oxígeno , Adolescente , Adulto , Biomarcadores/análisis , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Adulto Joven
15.
Int J Sports Physiol Perform ; 16(12): 1764-1776, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34044369

RESUMEN

PURPOSE: This study aimed to determine the effects of an acute "train-low" nutritional protocol on markers of recovery optimization compared to standard recovery nutrition protocol. METHODS: After completing a 2-hour high-intensity interval running protocol, 8 male endurance athletes consumed a standard dairy milk recovery beverage (CHO; 1.2 g/kg body mass [BM] of carbohydrate and 0.4 g/kg BM of protein) and a low-carbohydrate (L-CHO; isovolumetric with 0.35 g/kg BM of carbohydrate and 0.5 g/kg BM of protein) dairy milk beverage in a double-blind randomized crossover design. Venous blood and breath samples, nude BM, body water, and gastrointestinal symptom measurements were collected preexercise and during recovery. Muscle biopsy was performed at 0 hour and 2 hours of recovery. Participants returned to the laboratory the following morning to measure energy substrate oxidation and perform a 1-hour distance test. RESULTS: The exercise protocol resulted in depletion of muscle glycogen stores (250 mmol/kg dry weight) and mild body-water losses (BM loss = 1.8%). Neither recovery beverage replenished muscle glycogen stores (279 mmol/kg dry weight) or prevented a decrease in bacterially stimulated neutrophil function (-21%). Both recovery beverages increased phosphorylation of mTORSer2448 (main effect of time = P < .001) and returned hydration status to baseline. A greater fold increase in p-GSK-3ßSer9/total-GSK-3ß occurred on CHO (P = .012). Blood glucose (P = .005) and insulin (P = .012) responses were significantly greater on CHO (618 mmol/L per 2 h and 3507 µIU/mL per 2 h, respectively) compared to L-CHO (559 mmol/L per 2 h and 1147 µIU/mL per 2 h, respectively). Rates of total fat oxidation were greater on CHO, but performance was not affected. CONCLUSION: A lower-carbohydrate recovery beverage consumed after exercise in a "train-low" nutritional protocol does not negatively impact recovery optimization outcomes.


Asunto(s)
Carbohidratos de la Dieta , Resistencia Física , Atletas , Estudios Cruzados , Carbohidratos de la Dieta/metabolismo , Método Doble Ciego , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/farmacología , Humanos , Masculino , Músculo Esquelético/fisiología , Resistencia Física/fisiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-33913436

RESUMEN

SUMMARY: Primary hyperparathyroidism requires a surgical approach to achieve a long-term cure. However, post-surgical recurrence significantly complicates the management of this condition. A number of causes for recurrent disease are well understood and several diagnostic modalities exist to localise the culprit parathyroid adenoma although none of them is efficacious in localisation of the recurrent lesion. In this case report, we highlight a novel causative mechanism and describe a unique diagnostic sequence that enabled curative treatment to be delivered. LEARNING POINTS: In the case described herein, we describe a novel location for a parathyroid adenoma causing recurrent PHPT. The case elucidates well the difficulties presented by such cases in terms of surgical planning and show the utility of PVS in such cases. Based on this case, we make the following recommendations: Meticulous care must be taken to prevent seeding of adenomatous tissue during primary excision. To consider the use of PVS in patients with discordant imaging in the setting of recurrent/persistent PHPT as a method to localise the causative adenoma. Same day PVS and surgery is a viable option for patients who either represent an anaesthetic risk or who are extremely anxious about the prospect of two separate procedures. Disordered calcium homeostasis is an important but forgotten cause of dysphagia which can be extremely debilitating for affected patients.

17.
Front Physiol ; 12: 628863, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33613323

RESUMEN

We compared the impact of two different, but commonly consumed, beverages on integrative markers of exercise recovery following a 2 h high intensity interval exercise (i.e., running 70-80% V̇O2 max intervals and interspersed with plyometric jumps). Participants (n = 11 males, n = 6 females) consumed a chocolate flavored dairy milk beverage (CM: 1.2 g carbohydrate/kg BM and 0.4 g protein/kg BM) or a carbohydrate-electrolyte beverage (CEB: isovolumetric with 0.76 g carbohydrate/kg BM) after exercise, in a randomized-crossover design. The recovery beverages were provided in three equal boluses over a 30 min period commencing 1 h post-exercise. Muscle biopsies were performed at 0 h and 2 h in recovery. Venous blood samples, nude BM and total body water were collected before and at 0, 2, and 4 h recovery. Gastrointestinal symptoms and breath hydrogen (H2) were collected before exercise and every 30 min during recovery. The following morning, participants returned for performance assessment. In recovery, breath H2 reached clinical relevance of >10 ppm following consumption of both beverages, in adjunct with high incidence of gastrointestinal symptoms (70%), but modest severity. Blood glucose response was greater on CEB vs. CM (P < 0.01). Insulin response was greater on CM compared with CEB (P < 0.01). Escherichia coli lipopolysaccharide stimulated neutrophil function reduced on both beverages (49%). p-GSK-3ß/total-GSK-3ß was greater on CM compared with CEB (P = 0.037); however, neither beverage achieved net muscle glycogen re-storage. Phosphorylation of mTOR was greater on CM than CEB (P < 0.001). Fluid retention was lower (P = 0.038) on CEB (74.3%) compared with CM (82.1%). Physiological and performance outcomes on the following day did not differ between trials. Interconnected recovery optimization markers appear to respond differently to the nutrient composition of recovery nutrition, albeit subtly and with individual variation. The present findings expand on recovery nutrition strategies to target functionality and patency of the gastrointestinal tract as a prerequisite to assimilation of recovery nutrition, as well as restoration of immunocompetency.

18.
Physiol Rep ; 9(1): e14660, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33400856

RESUMEN

Chronic sleep loss is a potent catabolic stressor, increasing the risk of metabolic dysfunction and loss of muscle mass and function. To provide mechanistic insight into these clinical outcomes, we sought to determine if acute sleep deprivation blunts skeletal muscle protein synthesis and promotes a catabolic environment. Healthy young adults (N = 13; seven male, six female) were subjected to one night of total sleep deprivation (DEP) and normal sleep (CON) in a randomized cross-over design. Anabolic and catabolic hormonal profiles were assessed across the following day. Postprandial muscle protein fractional synthesis rate (FSR) was assessed between 13:00 and 15:00 and gene markers of muscle protein degradation were assessed at 13:00. Acute sleep deprivation reduced muscle protein synthesis by 18% (CON: 0.072 ± 0.015% vs. DEP: 0.059 ± 0.014%·h-1 , p = .040). In addition, sleep deprivation increased plasma cortisol by 21% (p = .030) and decreased plasma testosterone by 24% (p = .029). No difference was found in the markers of protein degradation. A single night of total sleep deprivation is sufficient to induce anabolic resistance and a procatabolic environment. These acute changes may represent mechanistic precursors driving the metabolic dysfunction and body composition changes associated with chronic sleep deprivation.


Asunto(s)
Hidrocortisona/sangre , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Privación de Sueño/metabolismo , Testosterona/sangre , Adulto , Femenino , Humanos , Masculino , Músculo Esquelético/patología , Proteolisis , Privación de Sueño/sangre , Adulto Joven
19.
Mol Metab ; 43: 101110, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33137489

RESUMEN

OBJECTIVE: Sleep loss has emerged as a risk factor for the development of impaired glucose tolerance. The mechanisms underpinning this observation are unknown; however, both mitochondrial dysfunction and circadian misalignment have been proposed. Because exercise improves glucose tolerance and mitochondrial function, and alters circadian rhythms, we investigated whether exercise may counteract the effects induced by inadequate sleep. METHODS: To minimize between-group differences of baseline characteristics, 24 healthy young males were allocated into one of the three experimental groups: a Normal Sleep (NS) group (8 h time in bed (TIB) per night, for five nights), a Sleep Restriction (SR) group (4 h TIB per night, for five nights), and a Sleep Restriction and Exercise group (SR+EX) (4 h TIB per night, for five nights and three high-intensity interval exercise (HIIE) sessions). Glucose tolerance, mitochondrial respiratory function, sarcoplasmic protein synthesis (SarcPS), and diurnal measures of peripheral skin temperature were assessed pre- and post-intervention. RESULTS: We report that the SR group had reduced glucose tolerance post-intervention (mean change ± SD, P value, SR glucose AUC: 149 ± 115 A.U., P = 0.002), which was also associated with reductions in mitochondrial respiratory function (SR: -15.9 ± 12.4 pmol O2.s-1.mg-1, P = 0.001), a lower rate of SarcPS (FSR%/day SR: 1.11 ± 0.25%, P < 0.001), and reduced amplitude of diurnal rhythms. These effects were not observed when incorporating three sessions of HIIE during this period (SR+EX: glucose AUC 67 ± 57, P = 0.239, mitochondrial respiratory function: 0.6 ± 11.8 pmol O2.s-1.mg-1, P = 0.997, and SarcPS (FSR%/day): 1.77 ± 0.22%, P = 0.971). CONCLUSIONS: A five-night period of sleep restriction leads to reductions in mitochondrial respiratory function, SarcPS, and amplitude of skin temperature diurnal rhythms, with a concurrent reduction in glucose tolerance. We provide novel data demonstrating that these same detrimental effects are not observed when HIIE is performed during the period of sleep restriction. These data therefore provide evidence in support of the use of HIIE as an intervention to mitigate the detrimental physiological effects of sleep loss.


Asunto(s)
Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Privación de Sueño/fisiopatología , Adulto , Glucemia/metabolismo , Metabolismo de los Hidratos de Carbono/fisiología , Ritmo Circadiano/fisiología , Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Voluntarios Sanos , Humanos , Masculino , Mitocondrias/metabolismo , Células Musculares/metabolismo , Biosíntesis de Proteínas , Sarcómeros/metabolismo , Sueño/fisiología , Privación de Sueño/metabolismo
20.
Phlebology ; 35(9): 706-714, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32611228

RESUMEN

OBJECTIVES: Venous thromboembolism is a potentially fatal complication of superficial endovenous treatment. Proper risk assessment and thromboprophylaxis could mitigate this hazard; however, there are currently no evidence-based or consensus guidelines. This study surveyed UK and Republic of Ireland vascular consultants to determine areas of consensus. METHODS: A 32-item survey was sent to vascular consultants via the Vascular and Endovascular Research Network (phase 1). These results generated 10 consensus statements which were redistributed (phase 2). 'Good' and 'very good' consensus were defined as endorsement/rejection of statements by >67% and >85% of respondents, respectively. RESULTS: Forty-two consultants completed phase 1. This generated seven statements regarding risk factors mandating peri-procedural pharmacoprophylaxis and three statements regarding specific pharmacoprophylaxis regimes. Forty-seven consultants completed phase 2. Regarding venous thromboembolism risk factors mandating pharmacoprophylaxis, 'good' and 'very good' consensus was achieved for 5/7 and 2/7 statements, respectively. Regarding specific regimens, 'very good' consensus was achieved for 3/3 statements. CONCLUSIONS: The main findings from this study were that there was 'good' or 'very good' consensus that patients with any of the seven surveyed risk factors should be given pharmacoprophylaxis with low-molecular-weight heparin. High-risk patients should receive one to two weeks of pharmacoprophylaxis rather than a single dose.


Asunto(s)
Tromboembolia Venosa , Anticoagulantes , Heparina de Bajo-Peso-Molecular/efectos adversos , Humanos , Irlanda/epidemiología , Factores de Riesgo , Reino Unido , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control
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