Rest Trial Research Articles

Listening to motivational music mitigates heat-related reductions in exercise performance

PurposeTo examine whether listening to motivational music mitigates heat-related reductions in exercise performance, and leads to a greater increase in thermal and cardiovascular strain. MethodsTwelve participants (26 ± 5 y, 77.5 ± 17.0 kg, 49 ± 8 ml·min−1·kg−1) completed 30-min of cycling preload at 50% VO2max followed by a 5-min rest and 15-min cycling time trial on seven separate occasions; three familiarisation sessions in a 20 °C room and four experimental trials in a climatic chamber regulated at either 21 °C, 50%RH (NEU) or 36 °C, 50%RH (HOT), each with and without the participant listening to self-selected motivational music during the 5-min rest and 15-min time trial. Measures of total work, core temperature and heart rate and blood pressure (from which rate-pressure product for cardiovascular strain was calculated), were recorded. ResultsWithout music, total work was lower (p < .001) in the HOT condition (168 ± 59 kJ) relative to the NEU condition (193 ± 60 kJ). With music, total work was greater relative to no music in both the NEU condition (203 ± 60 kJ vs 193 ± 60 kJ; p = .008) and HOT condition (183 ± 63 kJ vs 168 ± 60 kJ; p = .029). The greater total work in the HOT condition with music relative to no music resulted in a higher (p = .006) core temperature (38.7 ± 0.4 °C vs 38.6 ± 0.5 °C) and a higher (p < .001) rate-pressure product (34.8 ± 7.1 mmHg·beats·min−1·10−3 vs 27.8 ± 3.7 mmHg·beats·min−1·10−3). ConclusionListening to motivational music mitigated heat-related reductions in exercise performance with an improvement in performance in the heat of ~10%. This improved exercise performance led to a greater increase in thermal and cardiovascular strain in the heat but did not exceed levels typically associated with an elevated health risk in a young, healthy population.

Impact Of Exercise Intensity And Resting Intervals During Resistance Exercise On Acute Sparc Secretion In Healthy Young Males: A Pilot Study

PURPOSE: Recently, it is going noteworthy that an exercise-induced novel myokine, secreted protein acidic and rich in cysteine (SPARC) has the potential to prevent colon cancer. Moreover, regular resistance exercise (RE) has been known to reduce the mortality risk of cancer. From these points of view, RE might prevent colon tumorigenesis via increasing SPARC, while it is unclear whether resistance exercise can promote SPARC secretion in human. Thus, the purpose of this study was to investigate the both effects of exercise intensity and duration of rest interval between exercise sets on acute response of RE-induced SPARC secretion. METHODS: We designed two experiments in this study. In study 1, 7 subjects completed three experiments in a random order. They performed two RE at both 70% (High) and 35% (Low) of the individual’s one repetition maximum (1-RM), and stayed rest condition without RE (Rest). The RE consisted of 8 kinds of exercise (double arm curl, shoulder press, double knee extension, chest press, lat-pull down, triceps press down, parallel squat, and seated rowing), for 3 sets of 7 repetitions. We recruited different 7 subjects in study 2, and let them conduct three experiments in a random order: RE (the same 8 kinds of exercise as described in study 1, 16 repetitions × 3 sets at 50% 1-RM) with long inter-set rest interval (LIE, 150 s), RE with short inter-set rest interval (SIE, 50 s), and rest with no-exercise (NE). Blood samples were obtained before, immediate after, and 1h after RE in both study. RESULTS: In study 1, serum SPARC concentration immediately after RE was significantly increased from baseline in High trial (P < 0.05), and that level was significantly higher than those in Rest and Low trials (P < 0.05, in both). In study 2, serum SPARC level immediately after RE in SIE trial significantly elevated compared with baseline (P < 0.05), and the increase was also significantly higher than NE trial (P < 0.05). However, the elevated SPARC concentrations in both High and SIE trials were swiftly returned to baseline within 1 h after RE. CONCLUSIONS: Our findings indicate that RE can induce temporally SPARC secretion. It is also conceivable that increasing exercise load and/or shortening rest intervals between exercise sets during RE might enhance SPARC production.

Low-intensity exercise delays the shivering response to core cooling.

Hypothermia can occur during aquatic exercise despite production of significant amounts of heat by the active muscles. Because the characteristics of human thermoregulatory responses to cold during exercise have not been fully elucidated, we investigated the effect of low-intensity exercise on the shivering response to core cooling in cool water. Eight healthy young men (24 ± 3 yr) were cooled through cool water immersion while resting (rest trial) and during loadless pedaling on a water cycle ergometer (exercise trial). Before the cooling, body temperature was elevated by hot water immersion to clearly detect a core temperature at which shivering initiates. Throughout the cooling period, mean skin temperature remained around the water temperature (25°C) in both trials, whereas esophageal temperature (Tes) did not differ between the trials (P > 0.05). The Tes at which oxygen uptake (V̇o2) rapidly increased, an index of the core temperature threshold for shivering, was lower during exercise than rest (36.2 ± 0.4°C vs. 36.5 ± 0.4°C, P < 0.05). The sensitivity of the shivering response, as indicated by the slope of the Tes-V̇o2 relation, did not differ between the trials (-441.3 ±177.4 ml·min-1·°C-1 vs. -411.8 ± 268.1 ml·min-1·°C-1, P > 0.05). The thermal sensation response to core cooling, assessed from the slope and intercept of the regression line relating Tes and thermal sensation, did not differ between the trials (P > 0.05). These results suggest that the core temperature threshold for shivering is delayed during low-intensity exercise in cool water compared with rest although shivering sensitivity is unaffected.

An audit of thoracic radiotherapy in extensive stage small cell lung cancer delivered as per REST trial protocol

An audit of thoracic radiotherapy in extensive stage small cell lung cancer delivered as per REST trial protocol

Prefrontal high gamma during a magnetoencephalographic working memory task.

In human electrophysiology research, the high gamma part of the power spectrum (~>60 Hz) is a relatively new area of investigation. Despite a low signal-to-noise ratio, evidence exists that it contains significant information about activity in local cortical networks. Here, using magnetoencephalography (MEG), we found high gamma activity when comparing data from an n-back working memory task to resting data in a large sample of normal volunteers. Initial analysis of power spectra from 0-back, 2-back, and rest trials showed three frequency bands exhibiting task-related differences: alpha, beta, and high gamma. Unlike alpha and beta, the high gamma spectrum was broad, without a peak at a single frequency. In addition, power in high gamma was highest for the 2-back and lowest during rest, while the opposite pattern occurred in the other bands. Beamformer source localization of each of the three frequency bands revealed a distinct set of sources for high gamma. These included several regions of prefrontal cortex that exhibited greater power when both n-back conditions were compared to rest. A subset of these regions had more power when the 2-back was compared to 0-back, which indicates a role in working memory performance. Our results show that high gamma will be important for understanding cortical processing during cognitive and other tasks. Furthermore, data from human intracortical recordings suggest that high gamma is the aggregate of spiking in local cortical networks, which implies that MEG could serve to bridge experimental modalities by noninvasively observing task-related modulation of spiking rates.

Nonoperative Management of Femoroacetabular Impingement: A Prospective Study

Background: The literature has given little attention to the nonoperative management of femoroacetabular impingement (FAI) syndrome despite a rapidly expanding body of research on the topic. Purpose: To perform a prospective study utilizing a nonoperative protocol on a consecutive series of patients presenting to our clinic with FAI syndrome. Study Design: Cohort study; Level of evidence, 2. Methods: Between 2013 and 2016, patients meeting the following criteria were prospectively recruited in a nonoperative FAI study: no prior hip surgery, groin-based pain, a positive impingement test, and radiographic FAI syndrome. The protocol consisted of an initial trial of rest, physical therapy, and activity modification. Patients who remained symptomatic were then offered an image-guided intra-articular steroid injection. Patients with recurrent symptoms were then offered arthroscopic treatment. Outcome scores were collected at 12 and 24 months. Statistical analysis was performed to identify risk factors for the need for operative treatment and to determine patient outcomes based on FAI type and treatment. Results: Ninety-three hips (n = 76 patients: mean age, 15.3 years; range, 10.4-21.4 years) were included in this study and followed for a mean ± SD 26.8 ± 8.3 months. Sixty-five hips (70%) were managed with physical therapy, rest, and activity modification alone. Eleven hips (12%) required a steroid injection but did not progress to surgery. Seventeen hips (18%) required arthroscopic management. All 3 groups saw similar improvements in modified Harris Hip Score (P = .961) and nonarthritic hip score (P = .975) with mean improvements of 20.3 ± 16.8 and 13.2 ± 15.5, respectively. Hips with cam impingement and combined cam-pincer impingement were 4.0 times more likely to meet the minimal clinically important difference in modified Harris Hip Score (P = .004) and 4.4 times more likely to receive surgical intervention (P = .05) than patients with pincer deformities alone. Participants in team sports were 3.0 times more likely than individual sport athletes to return to competitive activities (P = .045). Conclusion: A majority (82%) of adolescent patients presenting with FAI syndrome can be managed nonoperatively, with significant improvements in outcome scores at a mean follow-up of 2 years. Clinical Relevance: A nonoperative approach should be the first-line treatment for young active patients with symptomatic FAI syndrome.

Non-Operative Management of Femoroacetabular Impingement: A Prospective Study

Objectives:Little attention has been given to the non-operative management of femoroacetabular impingement (FAI) in the literature despite a rapidly expanding body of research on the topic. The purpose of the current project was to perform a prospective study utilizing a non-operative protocol on a consecutive series of patients presenting to our clinic with FAI.Methods:Between 2013 and 2016, patients referred to our clinic for hip pain that had a positive impingement sign were prospectively recruited in a non-operative FAI study. The protocol consisted of an initial trial of rest, physical therapy, and activity modification with a focus on avoidance of high hip flexion (Activity Mod group). Patients who remained symptomatic were then treated with an image-guided intra-articular steroid injection (Injection group). Patients with residual symptoms were then offered arthroscopic treatment (Surgery group). Outcome scores were collected at 12 and 24 months. Statistical analysis was performed to identify risk factors for failure of non-operative treatment.Results:129 symptomatic hips in 100 patients were enrolled. After our exclusion criteria were applied, 110 hips in 84 patients remained with a mean follow-up of 25.5 months. Eighty-one hips (73.6%) were managed with PT, rest, and activity modification alone. Thirteen hips (11.8%) required a steroid injection, but did not progress to surgery. Sixteen hips (14.5%) required arthroscopic management. All three groups saw similar improvements in modified Harris hip score (mHHS)(p=0.706) and non-arthritic hips score (NAHS)(p=0.712). Initial, and most recent, mHHS and NAHS can be found in Table 1. Labral tears were distributed similarly among the three groups (n=41, p=0.09) and saw similar improvements in outcomes (p>0.5) as hips without labral tears. The surgical patients attempted non-operative treatment for a mean of 8.8 months prior to surgical intervention. Delays in surgery were not associated with worse outcomes. Cam lesion size, acetabular coverage, and the presence of a labral tear were not associated with non-operative treatment failure (p=0.579).Conclusion:A large majority of adolescent patients presenting with FAI can be managed nonoperatively with significant improvements in outcomes scores and continuation of sport at a mean follow up of two years. This is the first prospective study evaluating the outcomes of a standardized non-operative protocol for the management of FAI. Our results show that a commitment to non-operative care can work for a large percentage of patients. We will be following these patients further into the future to examine the durability of these results.Table 1.Mean±Standard deviation of intial and most recent modified Harris hip score and non-arthritic hip score.Modified Harris Hip ScoreNon-Arthritic Hip ScoreInitialMost RecentInitialMost RecentActivity Mod70.0+13.389.8+12.274.2+16.487.1+14.8Injection67.9+11.291.3+9.272.2+13.186.1+10.2Scope67.6+9.387.9+11.472.7+11.389.2+9.3p-value0.7480.6760.699 0.433

Detection of Functional Overreaching in Endurance Athletes Using Proteomics

There is a strong demand for diagnostic tools to identify athletes in various training states. PURPOSE: To determine if a cluster of proteins could be identified through proteomics procedures that are linked to functional overreaching (FOR) in male endurance athletes. METHODS: Participants (N=10, age 38.3±3.4 y, VO2max 41.3±1.7 ml.kg-1.min-1) served as their own controls and in random, counterbalanced order either ran/cycled 2.5 h (70.0±3.7% VO2max, 79.6±6.3% HRmax) three days in a row (FOR) or sat in the lab (rest) (separated by three weeks) (7:00 - 9:30 am, overnight fasted state). Participants provided fingerprick samples for dried blood spot samples (DBS) pre- and post-exercise/rest each of the three days, and then at 7:00 am during two additional recovery days. Participants also completed the Training Distress Scale (TDS) (19-items) at 7:00 am each of the five mornings during each trial (FOR and rest). Proteins were solubilized from DBS, digested into peptides and measured with nanoLC-MS in data independent acquisition mode (Q-Exactive, Thermo Fisher Scientific, Waltham, MA). The RAW MS data files were processed using SpectronautTM software (Biognosys, Schlieren, Switzerland). Following data independent acquisition (DIA method), 594 proteins were identified and quantified. Proteins were considered for the FOR cluster if they were elevated during one of the two recovery days but not more than one of the exercise days (compared to rest). The Generalized Estimating Equation (GEE) was used to identify proteins linked to FOR (between trial contrasts, P≤0.05 for proteins with CV<15%, P≤0.01 with CV>15%). RESULTS: TDS scores differed between FOR and rest trials, peaking on the first recovery day (9.8±3.8, 3.5±2.6, respectively, P=0.029). A total of 13 proteins was linked to FOR and of these, 11 were related to the immune system, and two to exercise-induced physiological responses. Immune-related proteins included those associated primarily with the acute phase response, complement activation, and granulocyte function. CONCLUSIONS: This study utilized targeted, DIA proteomics procedures to identify a cluster of 13 proteins linked to FOR (7.5 h of high intensity exercise over three days), and 85% of the proteins were related to immune system activation during the 2-day recovery period.

Effect of downhill walking on next-day muscle damage and glucose metabolism in healthy young subjects

This study aimed to investigate the effect of downhill walking on muscle damage and glucose metabolism in healthy subjects. All ten healthy young men and women (age, 24.0 ± 1.4years) performed rest, uphill walking, and downhill walking trials. In the exercise trials, uphill (+5%) or downhill (-5%) treadmill walking was performed at 6km/h for 30min. On the next day, muscle soreness was significantly higher in the downhill trial than in the uphill trial (P < 0.01). Respiratory metabolic performance did not differ between trials. However, carbohydrate oxidation was negatively correlated with plasma creatine kinase (r = -0.41) and muscle soreness (r = -0.47). Fasting blood glucose was significantly lower in the uphill trial than in the rest trial (P < 0.01) but not in the downhill trial. These observations suggest that downhill but not uphill walking causes mild delayed-onset muscle damage, which did not cause marked impairment in glucose metabolism. However, higher muscle damage responders might exhibit lower glucose metabolism.

(203) - Within session reliability of conditioned pain modulation in young healthy adults depends on location of test stimulus

The aim of this repeatability study was to investigate the between and within session reliability of conditioned pain modulation (CPM) in young healthy individuals. Thirty subjects (19.3 ± 1.5 years; 15 females) participated in two randomized sessions separated by approximately one week. During each session, pressure pain thresholds (PPTs) at the right quadriceps and upper trapezius muscles were assessed before and during ice water immersion (left foot, 0 ± 1°C, 105 ± 18 seconds). In one of the sessions, the CPM protocol was repeated following 23 minute quiet rest. Percentage change in CPM within and between sessions at each assessment site were compared with repeated measures ANOVAs. Intraclass correlations (ICCs (3,k)) with 95% confidence interval (CI) as a measure of relative reliability were computed within and between sessions for each assessment site. During submersion of foot in the ice water bath, participants reported moderate-to-severe peak pain intensity (6.6 ± 1.8 using 0/10 Numerical Rating Scale). Peak pain intensity decreased significantly between sessions (7.0 ± 1.0 to 6.4 ± 1.7; P = .01) but was similar within session (P > .05). PPTs significantly increased during cold pressor tests compared to baseline without ice (P < .001). The CPM response decreased at the quadriceps and upper trapezius muscles similarly following quiet rest compared with before quiet rest (trial: P < .05; trial x site: P > .05). Despite the decrease, CPM had a fair-to-good within session reliability; although this differed based on the location of the test stimulus (ICCs: quadriceps = .707 [.395–.859]; upper trapezius = .433 [−.190–.730]). Between-session reliability was poor at both assessment sites (ICCs: quadriceps = .208 [−.715–.628]; upper trapezius = .350 [−.401–.694]). These results suggest that CPM is not fully restored following a 23-minute washout period and reliability of CPM may change depending on location of the test stimulus. Future studies are needed to investigate the factors involved in CPM reliability.

EEG Classification of Covert Speech Using Regularized Neural Networks

Communication using brain–computer interfaces (BCIs) can be non-intuitive, often requiring the performance of a conversation-irrelevant task such as hand motor imagery. In this paper, the reliability of electroencephalography (EEG) signals in discriminating between different covert speech tasks is investigated. Twelve participants, across two sessions each, were asked to perform multiple iterations of three differing mental tasks for 10 s each: unconstrained rest or the mental repetition of the words “yes” or “no.” A multilayer perceptron (MLP) artificial neural network (ANN) was used to classify all three pairwise combinations of “yes,” “no,” and rest trials and also for ternary classification. An average accuracy of 75.7% ± 9.6 was reached in the classification of covert speech trials versus rest, with all participants exceeding chance level (57.8%). The classification of “yes” versus “no” yielded an average accuracy of 63.2 ± 6.4 with ten participants surpassing chance level (57.8%). Finally, the ternary classification yielded an average accuracy of 54.1% ± 9.7 with all participants exceeding chance level (39.1%). The proposed MLP network provided significantly higher accuracies compared to some of the most common classification techniques in BCI. To our knowledge, this is the first report of using ANN for the classification of EEG covert speech across multiple sessions. Our findings support further study of covert speech as a BCI activation task, potentially leading to the development of more intuitive BCIs for communication.

Acute exercise alters skeletal muscle mitochondrial respiration and H2O2 emission in response to hyperinsulinemic-euglycemic clamp in middle-aged obese men.

Obesity, sedentary lifestyle and aging are associated with mitochondrial dysfunction and impaired insulin sensitivity. Acute exercise increases insulin sensitivity in skeletal muscle; however, whether mitochondria are involved in these processes remains unclear. The aim of this study was to investigate the effects of insulin stimulation at rest and after acute exercise on skeletal muscle mitochondrial respiratory function (JO2) and hydrogen peroxide emission (JH2O2), and the associations with insulin sensitivity in obese, sedentary men. Nine men (means ± SD: 57 ± 6 years; BMI 33 ± 5 kg.m2) underwent hyperinsulinemic-euglycemic clamps in two separate trials 1–3 weeks apart: one under resting conditions, and another 1 hour after high-intensity exercise (4x4 min cycling at 95% HRpeak). Muscle biopsies were obtained at baseline, and pre/post clamp to measure JO2 with high-resolution respirometry and JH2O2 via Amplex UltraRed from permeabilized fibers. Post-exercise, both JO2 and JH2O2 during ADP stimulated state-3/OXPHOS respiration were lower compared to baseline (P<0.05), but not after subsequent insulin stimulation. JH2O2 was lower post-exercise and after subsequent insulin stimulation compared to insulin stimulation in the rest trial during succinate supported state-4/leak respiration (P<0.05). In contrast, JH2O2 increased during complex-I supported leak respiration with insulin after exercise compared with resting conditions (P<0.05). Resting insulin sensitivity and JH2O2 during complex-I leak respiration were positively correlated (r = 0.77, P<0.05). We conclude that in obese, older and sedentary men, acute exercise modifies skeletal muscle mitochondrial respiration and H2O2 emission responses to hyperinsulinemia in a respiratory state-specific manner, which may have implications for metabolic diseases involving insulin resistance.

Acute Hypotension after High-Intensity Interval Exercise in Metabolic Syndrome Patients.

The purpose of this study was to compare the magnitude of post-exercise hypotension (PEH) after a bout of cycling exercise using high-intensity interval training (HIIT) in comparison to a bout of traditional moderate-intensity continuous exercise (CE). After supine rest 14 obese (31±1 kg·m-2) middle-age (57±2 y) metabolic syndrome patients (50% hypertensive) underwent a bout of HIIT or a bout of CE in a random order and then returned to supine recovery for another 45 min. Exercise trials were isocaloric and compared to a no-exercise trial (CONT) of supine rest for a total of 160 min. Before and after exercise we assessed blood pressure (BP), heart rate (HR), cardiac output (Q), systemic vascular resistance (SVR), intestinal temperature (TINT), forearm skin blood flow (SKBF) and percent dehydration. HIIT produced a larger post-exercise reduction in systolic blood pressure than CE in the hypertensive group (-20±6 vs. -5±3 mmHg) and in the normotensive group (-8±3 vs. -3±2 mmHg) while HIIT reduced SVR below CE (P<0.05). Percent dehydration was larger after HIIT, and post-exercise TINT and SKBF increased only after HIIT (all P<0.05). Our findings suggest that HIIT is a superior exercise method to CE to acutely reduce blood pressure in MSyn subjects.

Development of an improved wearable device for core body temperature monitoring based on the dual heat flux principle

Objective: In this paper, a miniaturized wearable core body temperature (CBT) monitoring system based on the dual heat flux (DHF) principle was developed. Approach: By interspersing calcium carbonate powder in PolyDimethylsiloxane (PDMS), a reformative heat transfer medium was produced to reduce the thermal equilibrium time. Besides, a least mean square (LMS) algorithm based active noise cancellation (ANC) method was adopted to diminish the impact of ambient temperature fluctuations. Theoretical analyses, finite element simulation, experiments on a hot plate and human volunteers were performed. Main results: The results showed that the proposed system had the advantages of small size, reduced initial time (~23.5 min), and good immunity to fluctuations of the air temperature. For the range of 37–41 °C on the hot plate, the error compared with a Fluke high accuracy thermometer was 0.08 ± 0.20 °C. In the human experiments, the measured temperature in the rest trial (34 subjects) had a difference of 0.13 ± 0.22 °C compared with sublingual temperature, while a significant increase of 1.36 ± 0.44 °C from rest to jogging was found in the exercise trial (30 subjects). Significance: This system has the potential for reliable continuous CBT measurement in rest and can reflect CBT variations during exercise.

Sensory processing in Huntington's disease.

An intriguing electrophysiological feature of patients with Huntington's disease (HD) is the delayed latency and decreased amplitude of somatosensory long-latency evoked potentials (LLeps). We investigated whether such dysfunction was associated with delayed conscious perception of the sensory stimulus. Sixteen HD patients and 16 control subjects faced a computer screen showing the Libet's clock (Libet et al., 1983). In Rest trials, subjects had to memorize the position of the clock handle at perception of either electrical or thermal stimuli (AW). In React, additionally, they were asked to make a fist with their right hand, in a simple reaction time task (SRT). LLseps were recorded from Cz in both conditions. LLeps negative peak latency (N2) and SRT were abnormally delayed in patients in all conditions. AW was only abnormally prolonged in the React condition but the time difference between AW and the negative peak of the LLeps was not different in the two groups. There was a significant negative correlation between SRT and AW or LLeps amplitude in patients but not in healthy subjects. Our HD patients did not show abnormalities in conscious perception of sensory stimuli but their LLeps abnormalities were more marked when they had to react. This is compatible with failure to detect stimulus salience rather than with a cognitive defect. HD patients at early stages of the disease have preserved subjective perception of sensation but faulty sensorimotor integration.

The Effect of Handcycle Ergometer Exercise on Glucose Tolerance in Ambulatory and Non-Ambulatory Adolescents.

Whole body or leg exercise before a meal can increase insulin sensitivity, but it is unclear whether the same can occur with upper body exercise since a smaller muscle mass is activated. We measured the impact of a single session of handcycle exercise on glucose tolerance and insulin sensitivity. Nonambulatory (Non-Amb) adolescents with spina bifida or cerebral palsy (4F/3M), or ambulatory peers (Control, 4F/7M) completed 2 glucose tolerance tests on separate days, preceded by either rest or a 35-min bout of moderate-to-vigorous intermittent handcycle exercise. The Non-Amb group had higher body fat (mean ± SD: 38 ± 12%, Control: 24 ± 9, p = .041) but similar VO2peak (17.7 ± 6.1 ml/kg/min, Control: 21.1 ± 7.9). Fasting glucose and insulin were normal for all participants. Compared with the rest trial, exercise resulted in a reduction in glucose area under the curve (11%, p = .008) without a significant group x trial interaction and no difference in the magnitude of change between groups. Insulin sensitivity was increased 16% (p = .028) by exercise in the Control group but was not significantly changed in the Non-Amb group. A single bout of handcycle exercise improves glucose tolerance in adolescents with and without mobility limitations and could therefore help maintain or improve metabolic health.

Panax ginseng and salvia miltiorrhiza supplementation abolishes eccentric exercise-induced vascular stiffening: a double-blind randomized control trial.

BackgroundMuscle damage induced by unaccustomed or eccentric exercise results in delayed onset vascular stiffening. We tested the hypothesis that a 7-day supplementation of panax ginseng and salvia miltiorrhiza prior to an acute eccentric exercise could attenuate arterial stiffening.MethodsBy using a double-blind study placebo-controlled randomized design, subjects were randomly assigned to either the Chinese herb (N = 12) or the placebo group (N = 11) and performed a downhill running (eccentric exercise) trial and a control (seated rest) trial.ResultsMuscle soreness increased 1–2 days after exercise similarly in both groups, whereas the herb group demonstrated a faster recovery on active range of motion. Plasma creatine kinase concentration increased significantly at 24 h in both groups but the magnitude of increase was attenuated in the herb group. Arterial stiffness as measured by carotid-femoral pulse wave velocity increased significantly at 24 h in the placebo group but such increase was absent in the herb group. Flow-mediated dilation did not change in either group. Plasma concentrations of CRP and IL-6 increased in the placebo group but no such increases were observed in the herb group. Changes in arterial stiffness induced by eccentric exercise were associated with the corresponding changes in IL-6 (r = 0.46, P < 0.05).ConclusionsA short-term Chinese herb supplementation of panax ginseng and salvia miltiorrhiza ameliorated the delayed onset vascular stiffening induced by acute downhill running exercise.Trial registrationClinicalTrials.gov: NCT02007304. Registered Dec. 5, 2013)

Omega-3 fatty acid supplementation combined with acute aerobic exercise does not alter the improved post-exercise insulin response in normoglycemic, inactive and overweight men.

The aim of this study was to determine if omega-3 (n-3) supplementation combined with acute aerobic exercise would improve glucose and insulin responses in normoglycemic, inactive, overweight men. In a random order, ten inactive and normoglycemic men (30.6±10years, 85.4±11kg, 26.7±4 BMI) completed a rest (R) and exercise trial (EX) without n-3 supplementation. Following 42days of n-3 supplementation, participants again completed a rest (R+n-3) and exercise trial (EX+n-3) with continued n-3 supplementation. The exercise trial consisted of 3days of ~70% VO2peak for 60min/session. N-3 supplementation entailed 4.55g/day of n-3 (EPA 2.45g, DHA 1.61g). A 75g oral glucose tolerance (OGTT) test was administered 14-16h after each trial. Relative to R (35,278±9169pmol/L), EX without n-3 reduced the incremental area under the curve for insulin (iAUCinsulin) during an OGTT by 21.3% (27765±4925pmol/L, p=0.018) and 20.6% after the EX+n-3 trial (27,999±8370pmol/L; p=0.007). In addition, EX (96±21pmol/L; p=0.006) reduced C-peptide by 13.5% when compared to R (111±26pmol/L). No difference was observed between R and n-3 trials for iAUCinsulin and iAUCC-peptide. Only EX improved insulin sensitivity index by 5.6% (p=0.02) when compared to R. These data suggest that n-3 supplementation does not add any additional benefit beyond the exercise induced insulin responses in inactive men. Furthermore, n-3 supplementation alone does not appear to impair insulin action in normoglycemic, inactive, overweight men.

Resting-State Subjective Experience and EEG Biomarkers Are Associated with Sleep-Onset Latency.

Difficulties initiating sleep are common in several disorders, including insomnia and attention deficit hyperactivity disorder. These disorders are prevalent, bearing significant societal and financial costs which require the consideration of new treatment strategies and a better understanding of the physiological and cognitive processes surrounding the time of preparing for sleep or falling asleep. Here, we search for neuro-cognitive associations in the resting state and examine their relevance for predicting sleep-onset latency using multi-level mixed models. Multiple EEG recordings were obtained from healthy male participants (N = 13) during a series of 5 min eyes-closed resting-state trials (in total, n = 223) followed by a period–varying in length up to 30 min–that either allowed subjects to transition into sleep (“sleep trials,” nsleep = 144) or was ended while they were still awake (“wake trials,” nwake = 79). After both eyes-closed rest, sleep and wake trials, subjective experience was assessed using the Amsterdam Resting-State Questionnaire (ARSQ). Our data revealed multiple associations between eyes-closed rest alpha and theta oscillations and ARSQ-dimensions Discontinuity of Mind, Self, Theory of Mind, Planning, and Sleepiness. The sleep trials showed that the transition toward the first sleep stage exclusively affected subjective experiences related to Theory of Mind, Planning, and Sleepiness. Importantly, sleep-onset latency was negatively associated both with eyes-closed rest ratings on the ARSQ dimension of Sleepiness and with the long-range temporal correlations of parietal theta oscillations derived by detrended fluctuation analysis (DFA). These results could be relevant to the development of personalized tools that help evaluate the success of falling asleep based on measures of resting-state cognition and EEG biomarkers.

Ghrelin, GLP-1, and leptin responses during exposure to moderate hypoxia.

Severe hypoxia has been indicated to cause acute changes in appetite-related hormones, which attenuate perceived appetite. However, the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite have not been elucidated. Therefore, we examined the effects of moderate hypoxia on appetite-related hormonal regulation and perceived appetite. Eight healthy males (21.0 ± 0.6 years; 173 ± 2.3 cm; 70.6 ± 5.0 kg; 23.4 ± 1.1 kg/m(2)) completed two experimental trials on separate days: a rest trial in normoxia (FiO2 = 20.9%) and a rest trial in hypoxia (FiO2 = 15.0%). The experimental trials were performed over 7 h in an environmental chamber. Blood samples and scores of subjective appetite were collected over 7 h. Standard meals were provided 1 h (745 kcal) and 4 h (731 kcal) after initiating exposure to hypoxia or normoxia within the chamber. Although each meal significantly reduced plasma active ghrelin concentrations (P < 0.05), the response did not differ significantly between the trials over 7 h. No significant differences in the area under the curves for plasma active ghrelin concentrations over 7 h were observed between the two trials. No significant differences were observed in glucagon-like peptide 1 or leptin concentrations over 7 h between the trials. The subjective feeling of hunger and fullness acutely changed in response to meal ingestions. However, these responses were not affected by exposure to moderate hypoxia. In conclusion, 7 h of exposure to moderate hypoxia did not change appetite-related hormonal responses or perceived appetite in healthy males.