Monitoring fatigue state with heart rate-based and subjective methods during intensified training in recreational runners.

The purpose of this study was firstly to examine the sensitivity of heart rate (HR)-based and subjective monitoring markers to intensified endurance training; and secondly, to investigate the validity of these markers to distinguish individuals in different fatigue states. A total of 24 recreational runners performed a 3-week baseline period, a 2-week overload period, and a 1-week recovery period. Performance was assessed before and after each period with a 3000m running test. Recovery was monitored with daily orthostatic tests, nocturnal HR recordings, questionnaires, and exercise data. The participants were divided into subgroups (overreached/OR, n = 8; responders/RESP, n = 12) based on the changes in performance and subjective recovery. The responses to the second week of the overload period were compared between the subgroups. RESP improved their baseline 3000 m time (p < 0.001) after the overload period (-2.5 ± 1.0%), and the change differed (p < 0.001) from OR (0.6 ± 1.2%). The changes in nocturnal HR (OR 3.2 ± 3.1%; RESP -2.8 ± 3.7%, p = 0.002) and HR variability (OR -0.7 ± 1.8%; RESP 2.1 ± 1.6%, p = 0.011) differed between the subgroups. In addition, the decrease in subjective readiness to train (p = 0.009) and increase in soreness of the legs (p = 0.04) were greater in OR compared to RESP. Nocturnal HR, readiness to train, and exercise-derived HR-running power index had ≥85% positive and negative predictive values in the discrimination between OR and RESP individuals. In conclusion, exercise tolerance can vary substantially in recreational runners. The results supported the usefulness of nocturnal HR and subjective recovery assessments in recognizing fatigue states.

Endurance Training Improves Leg Proton Release and Decreases Potassium Release During High-Intensity Exercise in Normoxia and Hypobaric Hypoxia.

AIM: To assess the impact of endurance training on skeletal muscle release of H+ and K+. METHODS: Nine participants performed one-legged knee extension endurance training at moderate and high intensities (70%-85% of Wpeak), three to four sessions·week-1 for 6 weeks. Post-training, the trained and untrained (control) leg performed two-legged knee extension at low, moderate, and high intensities (40%, 62%, and 83% of Wpeak) in normoxia and hypoxia (~4000 m). The legs were exercised simultaneously to ensure identical arterial inflow concentrations of ions and metabolites, and identical power output was controlled by visual feedback. Leg blood flow was measured (ultrasound Doppler), and acid-base variables, lactate- and K+ concentrations were assessed in arterial and femoral venous blood to study K+ and H+ release. Ion transporter abundances were assessed in muscle biopsies. RESULTS: Lactate-dependent H+ release was similar in hypoxia to normoxia (p = 0.168) and was lower in the trained than the control leg at low-moderate intensities (p = 0.060-0.006) but similar during high-intensity exercise. Lactate-independent and total H+ releases were higher in hypoxia (p < 0.05) and increased more with power output in the trained leg (leg-by-power output interactions: p = 0.02). K+ release was similar at low intensity but lower in the trained leg during high-intensity exercise in normoxia (p = 0.024) and hypoxia (p = 0.007). The trained leg had higher abundances of Na+/H+ exchanger 1 (p = 0.047) and Na+/K+ pump subunit α (p = 0.036). CONCLUSION: Moderate- to high-intensity endurance training increases lactate-independent H+ release and reduces K+ release during high-intensity exercise, coinciding with increased Na+/H+ exchanger 1 and Na+/K+ pump subunit α muscle abundances.

The influence of endurance exercise training on myocardial fibrosis and arrhythmogenesis in a coxsackievirus B3 myocarditis mouse model.

Nonischaemic myocardial fibrosis is associated with cardiac dysfunction, malignant arrhythmias and sudden cardiac death. In the absence of a specific aetiology, its finding as late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging is often attributed to preceding viral myocarditis. Athletes presenting with ventricular arrhythmias often have nonischaemic LGE. Previous studies have demonstrated an adverse effect of exercise on the course of acute viral myocarditis. In this study, we have investigated, for the first time, the impact of endurance training on longer-term outcomes such as myocardial fibrosis and arrhythmogenicity in a murine coxsackievirus B3 (CVB)-induced myocarditis model. Male C57BL/6J mice (n = 72) were randomly assigned to 8 weeks of forced treadmill running (EEX) or no exercise (SED). Myocarditis was induced 2 weeks later by a single intraperitoneal injection with CVB, versus vehicle in the controls (PBS). In a separate study, mice (n = 30) were subjected to pretraining for 13 weeks (preEEX), without continuation of exercise during myocarditis. Overall, continuation of exercise resulted in a milder clinical course of viral disease, with less weight loss and better preserved running capacity. CVB-EEX and preEEX-CVB mice tended to have a lower mortality rate. At sacrifice (i.e. 6 weeks after inoculation), the majority of virus was cleared from the heart. Histological assessment demonstrated prominent myocardial inflammatory infiltration and cardiomyocyte loss in both CVB groups. Inflammatory lesions in the CVB-EEX group contained higher numbers of pro-inflammatory cells (iNOS-reactive macrophages and CD8+ T lymphocytes) compared to these in CVB-SED. Treadmill running during myocarditis increased interstitial fibrosis [82.4% (CVB-EEX) vs. 56.3% (CVB-SED); P = 0.049]. Additionally, perivascular and/or interstitial fibrosis with extensive distribution was more likely to occur with exercise [64.7% and 64.7% (CVB-EEX) vs. 50% and 31.3% (CVB-SED); P = 0.048]. There was a numerical, but not significant, increase in the number of scars per cross-section (1.9 vs. 1.2; P = 0.195), with similar scar distribution and histological appearance in CVB-EEX and CVB-SED. In vivo electrophysiology studies did not induce sustained monomorphic ventricular tachycardia, only nonsustained (usually polymorphic) runs. Their cumulative beat count and duration paralleled the increased fibrosis between CVB-EEX and CVB-SED, but the difference was not significant (P = 0.084 for each). Interestingly, in mice that were subjected to pretraining only without continuation of exercise during myocarditis, no differences between pretrained and sedentary mice were observed at sacrifice (i.e. 6 weeks after inoculation and training cessation) with regard to myocardial inflammation, fibrosis, and ventricular arrhythmogenicity. In conclusion, endurance exercise during viral myocarditis modulates the inflammatory process with more pro-inflammatory cells and enhances perivascular and interstitial fibrosis development. The impact on ventricular arrhythmogenesis requires further exploration.

Neuromuscular Adaptations in Endurance-Trained Male Adolescents Versus Untrained Peers: A 9-Month Longitudinal Study.

BACKGROUND: Neuromuscular function is considered as a determinant factor of endurance performance during adulthood. However, whether endurance training triggers further neuromuscular adaptations exceeding those of growth and maturation alone over the rapid adolescent growth period is yet to be determined. OBJECTIVE: The present study investigated the concurrent role of growth, maturation, and endurance training on neuromuscular function through a 9-month training period in adolescent triathletes. METHODS: Thirty-eight 13- to 15-year-old males (23 triathletes [~6 h/week endurance training] and 15 untrained [<2 h/week endurance activity]) were evaluated before and after a 9-month triathlon training season. Maximal oxygen uptake (V̇O2max) and power at V̇O2max were assessed during incremental cycling. Knee extensor maximal voluntary isometric contraction torque (MVCISO) was measured and the voluntary activation level (VAL) was determined using the twitch interpolation technique. Knee extensor doublet peak torque (T100Hz) and normalized vastus lateralis (VL) electromyographic activity (EMG/M-wave) were also determined. VL and rectus femoris (RF) muscle architecture was assessed using ultrasonography. RESULTS: Absolute V̇O2max increased similarly in both groups but power at V̇O2max only significantly increased in triathletes (+13.8%). MVCISO (+14.4%), VL (+4.4%), and RF (+15.8%) muscle thicknesses and RF pennation angle (+22.1%) increased over the 9-month period in both groups similarly (p < 0.01), although no changes were observed in T100Hz, VAL, or VL EMG/M-wave. No changes were detected in any neuromuscular variables, except for coactivation. CONCLUSION: Endurance training did not induce detectible, additional neuromuscular adaptations. However, the training-specific cycling power improvement in triathletes may reflect continued skill enhancement over the training period.

Astaxanthin Supplementation as a Potential Strategy for Enhancing Mitochondrial Adaptations in the Endurance Athlete: An Invited Review.

Astaxanthin, a potent antioxidant found in marine organisms such as microalgae and krill, may offer ergogenic benefits to endurance athletes. Originally used in fish feed, astaxanthin has shown a greater ability to mitigate various reactive oxygen species and maintain the structural integrity of mitochondria compared to other exogenous antioxidants. More recent work has shown that astaxanthin may improve: (1) cycling time trial performance, (2) cardiorespiratory measures such as submaximal heart rate during running or cycling, (3) recovery from delayed-onset muscle soreness, and (4) endogenous antioxidant capacity such as whole blood glutathione within trained populations. In this review, the history of astaxanthin and its chemical structure are first outlined before briefly describing the various adaptations (e.g., mitochondrial biogenesis, enhanced endogenous antioxidant capacity, etc.) which take place specifically at the mitochondrial level as a result of chronic endurance training. The review then concludes with the potential additive effects that astaxanthin may offer in conjunction with endurance training for the endurance athlete and offers some suggested practical recommendations for athletes and coaches interested in supplementing with astaxanthin.

Effects of endurance training under calorie restriction on energy substrate metabolism in mouse skeletal muscle and liver.

We investigated whether calorie restriction (CR) enhances metabolic adaptations to endurance training (ET). Ten-week-old male Institute of Cancer Research (ICR) mice were fed ad libitum or subjected to 30% CR. The mice were subdivided into sedentary and ET groups. The ET group performed treadmill running (20-25 m/min, 30 min, 5 days/week) for 5 weeks. We found that CR decreased glycolytic enzyme activity and monocarboxylate transporter (MCT) 4 protein content, while enhancing glucose transporter 4 protein content in the plantaris and soleus muscles. Although ET and CR individually increased citrate synthase activity in the plantaris muscle, the ET-induced increase in respiratory chain complex I protein content was counteracted by CR. In the soleus muscle, mitochondrial enzyme activity and protein levels were increased by ET, but decreased by CR. It has been suggested that CR partially interferes with skeletal muscle adaptation to ET.

Comparison of intramyocellular lipid metabolism in patients with diabetes and male athletes.

Despite opposing insulin sensitivity and cardiometabolic risk, both athletes and patients with type 2 diabetes have increased skeletal myocyte fat storage: the so-called "athlete's paradox". In a parallel non-randomised, non-blinded trial (NCT03065140), we characterised and compared the skeletal myocyte lipid signature of 29 male endurance athletes and 30 patients with diabetes after undergoing deconditioning or endurance training respectively. The primary outcomes were to assess intramyocellular lipid storage of the vastus lateralis in both cohorts and the secondary outcomes were to examine saturated and unsaturated intramyocellular lipid pool turnover. We show that athletes have higher intramyocellular fat saturation with very high palmitate kinetics, which is attenuated by deconditioning. In contrast, type 2 diabetes patients have higher unsaturated intramyocellular fat and blunted palmitate and linoleate kinetics but after endurance training, all were realigned with those of deconditioned athletes. Improved basal insulin sensitivity was further associated with better serum cholesterol/triglycerides, glycaemic control, physical performance, enhanced post insulin receptor pathway signalling and metabolic sensing. We conclude that insulin-resistant, maladapted intramyocellular lipid storage and turnover in patients with type 2 diabetes show reversibility after endurance training through increased contributions of the saturated intramyocellular fatty acid pools. Clinical Trial Registration: NCT03065140: Muscle Fat Compartments and Turnover as Determinant of Insulin Sensitivity (MISTY).

Temporal dynamics of the multi-omic response to endurance exercise training.

Regular exercise promotes whole-body health and prevents disease, but the underlying molecular mechanisms are incompletely understood1-3. Here, the Molecular Transducers of Physical Activity Consortium4 profiled the temporal transcriptome, proteome, metabolome, lipidome, phosphoproteome, acetylproteome, ubiquitylproteome, epigenome and immunome in whole blood, plasma and 18 solid tissues in male and female Rattus norvegicus over eight weeks of endurance exercise training. The resulting data compendium encompasses 9,466 assays across 19 tissues, 25 molecular platforms and 4 training time points. Thousands of shared and tissue-specific molecular alterations were identified, with sex differences found in multiple tissues. Temporal multi-omic and multi-tissue analyses revealed expansive biological insights into the adaptive responses to endurance training, including widespread regulation of immune, metabolic, stress response and mitochondrial pathways. Many changes were relevant to human health, including non-alcoholic fatty liver disease, inflammatory bowel disease, cardiovascular health and tissue injury and recovery. The data and analyses presented in this study will serve as valuable resources for understanding and exploring the multi-tissue molecular effects of endurance training and are provided in a public repository ( https://motrpac-data.org/ ).

Why are elite athletes prone to heart arrhythmias?

Studying cardiac effects of extreme exercise could yield clues to atrial fibrillation.

Circulating extracellular vesicle characteristics differ between men and women following 12 weeks of concurrent exercise training.

Concurrent resistance and endurance exercise training (CET) has well-studied benefits; however, inherent hormonal and genetic differences alter adaptive responses to exercise between sexes. Extracellular vesicles (EVs) are factors that contribute to adaptive signaling. Our purpose was to test if EV characteristics differ between men and women following CET. 18 young healthy participants underwent 12-weeks of CET. Prior to and following CET, subjects performed an acute bout of heavy resistance exercise (AHRET) consisting of 6 × 10 back squats at 75% 1RM. At rest and following AHRET, EVs were isolated from plasma and characteristics and miRNA contents were analyzed. AHRET elevated EV abundance in trained men only (+51%) and AHRET-induced changes were observed for muscle-derived EVs and microvesicles. There were considerable sex-specific effects of CET on EV miRNAs, highlighted by larger variation following the 12-week program in men compared to women at rest. Pathway analysis based on differentially expressed EV miRNAs predicted that AHRET and 12 weeks of CET in men positively regulates hypertrophy and growth pathways more so than in women. This report highlights sex-based differences in the EV response to resistance and concurrent exercise training and suggests that EVs may be important adaptive signaling factors altered by exercise training.

Does overreaching from endurance-based training impair sleep: A systematic review and meta-analysis.

BACKGROUND: Overreaching is often linked to a deterioration in sleep quality, yet a comprehensive review is lacking. The aim of this systemic review and meta-analysis was to synthesise the literature and quantify the effect of overreaching from endurance-based training on sleep quality. METHOD: The review was conducted following the PRISMA guidelines. The final search was conducted in May 2023 using four electronic databases (Web of Science Core Collection, MEDLINE, Cochrane Central Database, SPORTDiscus). Studies were included for a qualitative review, while random-effects meta-analyses were conducted for objective and subjective sleep. RESULTS AND DISCUSSION: The search returned 805 articles. Fourteen studies were included in the systematic review; Three and eight articles were eligible for the meta-analyses (objective and subjective, respectively). On average, the overreaching protocols were sixteen days in length (6 to 28 days) and included exercise modalities such as cycling (number of studies [k] = 5), rowing (k = 4), triathlon (k = 3), running (k = 2), and swimming (k = 1). Actigraphy was the only form of objective sleep measurement used across all studies (k = 3), while various instruments were used to capture subjective sleep quality (k = 13). When comparing objective sleep quality following the overreaching intervention to baseline (or a control), there was a significant reduction in sleep efficiency (mean difference = -2.0%; 95% CI -3.2, -0.8%; Glass' Δ = -0.83; p < 0.01). In contrast, when comparing subjective sleep quality following the overreaching intervention to baseline (or a control), there was no effect on subjective sleep quality (Glass' Δ = -0.27; 95% CI -0.79, 0.25; p = 0.08). Importantly, none of the included studies were judged to have a low risk of bias. While acknowledging the need for more high-quality studies, it appears that overreaching from endurance-based training can deteriorate objective sleep without influencing the perception of sleep quality. PROTOCOL REGISTRATION: This protocol was registered in The International Prospective Register of Systematic Reviews (PROSPERO) on 21st November 2022, with the registration number CRD42022373204.

The Influence of a Polyphenol-Rich Red Berry Fruit Juice on Recovery Process and Leg Strength Capacity after Six Days of Intensive Endurance Exercise in Recreational Endurance Athletes.

BACKGROUND: Various nutritional strategies are increasingly used in sports to reduce oxidative stress and promote recovery. Chokeberry is rich in polyphenols and can reduce oxidative stress. Consequently, chokeberry juices and mixed juices with chokeberry content are increasingly used in sports. However, the data are very limited. Therefore, this study investigates the effects of the short-term supplementation of a red fruit juice drink with chokeberry content or a placebo on muscle damage, oxidative status, and leg strength during a six-day intense endurance protocol. METHODS: Eighteen recreational endurance athletes participated in a cross-over high intensity interval training (HIIT) design, receiving either juice or a placebo. Baseline and post-exercise assessments included blood samples, anthropometric data, and leg strength measurements. RESULTS: A significant increase was measured in muscle damage following the endurance protocol in all participants (∆ CK juice: 117.12 ± 191.75 U/L, ∆ CK placebo: 164.35 ± 267.00 U/L; p = 0.001, η2 = 0.17). No group effects were detected in exercise-induced muscle damage (p = 0.371, η2 = 0.010) and oxidative status (p = 0.632, η2 = 0.000). The reduction in strength was stronger in the placebo group, but group effects are missing statistical significance (∆ e1RM juice: 1.34 ± 9.26 kg, ∆ e1RM placebo: -3.33 ± 11.49 kg; p = 0.988, η2 = 0.000). CONCLUSION: Although a reduction in strength can be interpreted for the placebo treatment, no statistically significant influence of chokeberry could be determined. It appears that potential effects may only occur with prolonged application and a higher content of polyphenols, but further research is needed to confirm this.

Endurance Training Inhibits the JAK2/STAT3 Pathway to Alleviate Sarcopenia.

Aging leads to a decrease in muscle function, mass, and strength in skeletal muscle of animals and humans. The transcriptome identified activation of the JAK/STAT pathway, a pathway that is associated with skeletal muscle atrophy, and endurance training has a significant effect on improving sarcopenia; however, the exact mechanism still requires further study. We investigated the effect of endurance training on sarcopenia. Six-month-old male SAMR1 mice were used as a young control group (group C), and the same month-old male SAMP8 mice were divided into an exercise group (group E) and a model group (group M). A 3-month running exercise intervention was performed on group E, and the other two groups were kept normally. Aging caused significant signs of sarcopenia in the SAMP8 mice, and endurance training effectively improved muscle function, muscle mass, and muscle strength in the SAMP8 mice. The expression of JAK2/STAT3 pathway factor was decreased in group E compared with group M, and the expression of SOCS3, the target gene of STAT3, and NR1D1, an atrophy-related factor, was significantly increased. Endurance training significantly improved the phenotypes associated with sarcopenia, and the JAK2/STAT3 pathway is a possible mechanism for the improvement of sarcopenia by endurance training, while NR1D1 may be its potential target. Keywords: Sarcopenia, Endurance training, Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3), Nuclear receptor subfamily 1, group D member 1 (Nr1d1).

Exercise addiction: a comparison between runners, cyclists, swimmers, and triathletes / Dependência ao exercício: uma comparação entre corredores, ciclistas, nadadores e triatletas / dicción al ejercicio: una comparación entre corredores, ciclistas, nadadores y triatletas

The aim of the present study was to evaluate and compare exercise addiction (EA) between runners, cyclists, swimmers, and triathletes. Took part in this study 39 runners, 32 cyclists, 30 swimmers and 38 triathletes. Exercise Dependence Scale (EDS), and the Exercise Addiction Inventory (EAI) was used to evaluate the EA and classified the participants into: at-risk for EA, nondependent-symptomatic, and nondependent-asymptomatic. Most participants were classified as nondependent symptomatic for EA. The EDS total score was significantly lower in the swimmers compared to the cyclists and triathletes and the EAI total score was significantly higher for cyclists compared to runners. Therefore, in both instruments, the majority of participants was nondependent symptomatic for EA (AU).

O objetivo do presente estudo foi avaliar e comparar a dependência ao exercício (DE) entre corredores, ciclistas, nadadores e triatletas. Participaram do estudo 39 corredores, 32 ciclistas, 30 nadadores e 38 triatletas. As escalas Exercise Dependence Scale (EDS) e Exercise Addiction Inventory (EAI) foram usadas para a avaliação da DE e classificaram os participantes em três categorias: em risco de DE, não dependente sintomático e não dependente assintomático. A maioria dos participantes foram classificadas como não dependentes sintomáticos para DE. O escore da EDS foi significativamente menor nos nadadores comparado aos ciclistas e triatletas e o escore total da EAI foi significantemente maior nos ciclistas comparado aos corredores. Portanto, em ambos os instrumentos, a maioria dos participantes foi não dependente sintomático para DE (AU).

El objetivo del presente estudio fue evaluar y comparar la adicción al ejercicio (AE) entre corredores, ciclistas, nadadores y triatletas. Participaron de este estudio 39 corredores, 32 ciclistas, 30 nadadores y 38 triatletas. La Escala de Dependencia al Ejercicio (EDS) y el Inventario de Adicción al Ejercicio (EAI) fueron utilizados para evaluar la AE y clasificaron a los participantes en tres categorías: en riesgo de AE, no dependiente-sintomático y no dependiente-asintomático. La mayoría de los participantes se clasificaron como no dependiente-sintomático para AE. La puntuación EDS fue significativamente menor en nadadores en comparación con ciclistas y triatletas y la puntuación EAI total fue significativamente mayor en ciclistas en comparación con corredores. Por lo tanto, en ambos instrumentos, la mayoría de los participantes eran sintomáticos no dependientes para AE

Endurance exercise associated with a fructooligosaccharide diet modulates gut microbiota and increases colon absorptive area.

BACKGROUND AND AIM: Fructooligosaccharide (FOS) supplementation can stimulate beneficial intestinal bacteria growth, but little is known about its influence on training performance. Therefore, this study analyzed FOS and exercise effects on gut microbiota and intestinal morphology of C57Bl/6 mice. METHODS: Forty male mice were divided into four groups: standard diet-sedentary (SDS), standard diet-exercised (SDE), FOS supplemented (7.5% FOS)-sedentary (FDS), and FOS supplemented-exercised (FDE), n = 10 each group. Exercise training consisted of 60 min/day, 3 days/week, for 12 weeks. RESULTS: SDE and FDE groups had an increase in aerobic performance compared to the pretraining period and SDS and FDS groups (P < 0.01), respectively. Groups with FOS increased colonic crypts size (P < 0.05). The FDE group presented rich microbiota (α-diversity) compared to other groups. The FDE group also acquired a greater microbial abundance (ß-diversity) than other groups. The FDE group had a decrease in the Ruminococcaceae (P < 0.002) and an increase in Roseburia (P < 0.003), Enterorhabdus (P < 0.004) and Anaerotruncus (P < 0.006). CONCLUSIONS: These findings suggest that aerobic exercise associated with FOS supplementation modulates gut microbiota and can increase colonic crypt size without improving endurance exercise performance.

Endurance training and hydroxyurea have synergistic effects on muscle function and energetics in sickle cell disease mice.

Sickle cell disease (SCD) is an hemoglobinopathy resulting in the production of an abnormal Hb (HbS) which can polymerize in deoxygenated conditions, leading to the sickling of red blood cells (RBC). These alterations can decrease the oxygen-carrying capacity leading to impaired function and energetics of skeletal muscle. Any strategy which could reverse the corresponding defects could be of interest. In SCD, endurance training is known to improve multiples muscle properties which restores patient's exercise capacity but present reduced effects in anemic patients. Hydroxyurea (HU) can increase fetal hemoglobin production which can reduce anemia in patients. The present study was conducted to determine whether HU can improve the effects of endurance training to improve muscle function and energetics. Twenty SCD Townes mice have been trained for 8 weeks with (n = 11) or without (n = 9) HU. SCD mice muscle function and energetics were analyzed during a standardized rest-exercise-recovery protocol, using Phosphorus-31 Magnetic resonance spectroscopy (31P-MRS) and transcutaneous stimulation. The combination of training and HU specifically decreased fatigue index and PCr consumption while muscle oxidative capacity was improved. These results illustrate the potential synergistic effects of endurance training and HU on muscle function and energetics in sickle cell disease.

The effect of craniocervical flexion and neck endurance exercises plus pulmonary rehabilitation on pulmonary function in spinal cord injury: a pilot single-blinded randomised controlled trial.

STUDY DESIGN: Randomised controlled trial with computerised allocation, assessor blinding and intention-to-treat analysis. OBJECTIVE: This study wanted to prove that cervicocranial flexion exercise (CCFE) and superficial neck flexor endurance training combined with common pulmonary rehabilitation is feasible for improving spinal cord injury people's pulmonary function. SETTING: Taoyuan General Hospital, Ministry of Health and Welfare: Department of Physiotherapy, Taiwan. METHOD: Thirteen individuals who had sustained spinal cord injury for less than a year were recruited and randomised assigned into two groups. The experimental group was assigned CCFEs and neck flexor endurance training plus normal cardiopulmonary rehabilitation. The control group was assigned general neck stretching exercises plus cardiopulmonary rehabilitation. Lung function parameters such as forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow rate (PEFR), inspiratory capacity (IC), dyspnoea, pain, and neck stiffness were recorded once a week as short-term outcome measure. RESULT: The experimental group showed significant time effects for FVC (pre-therapy: 80.4 ± 21.4, post-therapy: 86.9 ± 16.9, p = 0.021, 95% CI: 0.00-0.26) and PEFR (pre-therapy: 67.0 ± 33.4; post-therapy: 78.4 ± 26.9, p = 0.042, 95% CI: 0.00-0.22) after the therapy course. Furthermore, the experimental group showed significant time effects for BDI (experimental group: 6.3 ± 3.0; control group: 10.8 ± 1.6, p = 0.012, 95% CI: 0.00-0.21). CONCLUSION: The exercise regime for the experimental group could efficiently increase lung function due to the following three reasons: first, respiratory accessory muscle endurance increases through training. Second, posture becomes less kyphosis resulting increasing lung volume. Third, the ratio between superficial and deep neck flexor is more synchronised. IRB TRIAL REGISTRATION: TYGH108045. CLINICAL TRIAL REGISTRATION: NCT04500223.

No additive effect of creatine, caffeine, and sodium bicarbonate on intense exercise performance in endurance-trained individuals.

BACKGROUND: Athletes commonly use creatine, caffeine, and sodium bicarbonate for performance enhancement. While their isolated effects are well-described, less is known about their potential additive effects. METHODS: Following a baseline trial, we randomized 12 endurance-trained males (age: 25 ± 5 years, VO2max: 56.7 ± 4.6 mL kg-1 min-1; mean ± SD) and 11 females (age: 25 ± 3 years, VO2max: 50.2 ± 3.4 mL kg-1 min-1) to 5 days of creatine monohydrate (0.3 g kg-1 per day) or placebo loading, followed by a daily maintenance dose (0.04 g kg-1) throughout the study. After the loading period, subjects completed four trials in randomized order where they ingested caffeine (3 mg kg-1), sodium bicarbonate (0.3 g kg-1), placebo, or both caffeine and sodium bicarbonate before a maximal voluntary contraction (MVC), 15-s sprint, and 6-min time trial. RESULTS: Compared to placebo, mean power output during 15-s sprint was higher following loading with creatine than placebo (+34 W, 95% CI: 10 to 58, p = 0.008), but with no additional effect of caffeine (+10 W, 95% CI: -7 to 24, p = 0.156) or sodium bicarbonate (+5 W, 95% CI: -4 to 13, p = 0.397). Mean power output during 6-min time trial was higher with caffeine (+12 W, 95% CI: 5 to 18, p = 0.001) and caffeine + sodium bicarbonate (+8 W, 95% CI: 0 to 15, p = 0.038), whereas sodium bicarbonate (-1 W, 95% CI: -7 to 6, p = 0.851) and creatine (-6 W, 95% CI: -15 to 4, p = 0.250) had no effects. CONCLUSION: While creatine and caffeine can enhance sprint- and time trial performance, respectively, these effects do not seem additive. Therefore, supplementing with either creatine or caffeine appears sufficient to enhance sprint or short intense exercise performance.

Effects and long-term outcomes of endurance versus resistance training as an adjunct to standard medication in patients with stable COPD: a multicenter randomized trial.

BACKGROUND: Comparisons between endurance training (ET) and resistance training (RT) have produced equivocal findings in chronic obstructive pulmonary disease (COPD) patients. The purpose of our study is to investigate the effectiveness and long-term outcomes of adding ET and RT to conventional medical treatment in patients with COPD. A secondary objective is to investigate the clinical improvements resulting from exercise training in patients with different disease severities. METHODS: The study was a multicenter, prospective trial in people with stable COPD. The cohort was randomized to three groups: individualized medical treatment group (MT), MT + endurance training group (MT + ET) and MT + resistance training group (MT + RT). Exercise was performed 3 times weekly over a 12-week period. The endpoints of exercise capacity, health-related quality of life, COPD symptoms, lung function, and anxiety and depression questionnaires were re-evaluated at baseline, at the completion of the intervention and at 6 and 12-month follow-up. According to the COPD assessment tool offered by GOLD guidelines, patients were stratified into GOLD A and B groups and GOLD C and D groups for further subgroup analysis. RESULTS: The intention-to-treat (ITT) population included 366 patients, 328 of them completed the study protocol over 12 months (the PP-population). There were no significant differences in the primary outcome, quality of life, between patients who underwent medical treatment (MT) alone, MT + endurance training (MT + ET), or MT + resistance training (MT + RT) at the completion of the intervention, 6-, or 12-month follow-up. Additionally, no significant differences were observed between MT, MT + RT, or MT + ET groups concerning the primary outcome, exercise capacity (3MWD), after initial 3 months of intervention. However, a small statistically significant difference was noted in favor of MT + ET compared to MT + RT at 12 months (ITT: Δ3MWD in ET vs RT = 5.53 m, 95% confidence interval: 0.87 to 13.84 m, P = 0.03) (PP: Δ3MWD in ET vs RT = 7.67 m, 95% confidence interval: 0.93 to 16.27 m, P = 0.04). For patients in the GOLD C and D groups, improvement in quality of life following ET or RT was significantly superior to medical intervention alone. Furthermore, upon completion of the exercise regimen, RT exhibited a greater improvement in anxiety compared to ET in these patients (ITT: ΔHAD-A at 3-month: RT = -1.63 ± 0.31 vs ET = -0.61 ± 0.33, p < 0.01) (PP: ΔHAD-A at 3-month: RT = -1.80 ± 0.36 vs ET = -0.75 ± 0.37, p < 0.01). CONCLUSIONS: Our study presents evidence of the beneficial effects of ET and RT in combination with standard medical treatment, as well as the long-term effects over time after the intervention. While the statistically significant effect favoring ET over RT in terms of exercise capacity was observed, it should be interpreted cautiously. Patients in severe stages of COPD may derive greater benefits from either ET or RT and should be encouraged accordingly. These findings have implications for exercise prescription in patients with COPD. TRIAL REGISTRATION: ChiCTR-INR-16009892 (17, Nov, 2016).