Acute Session Research Articles

Is there spontaneous energy expenditure compensation in response to intensive exercise in obese youth?

Physical activity is mainly used in weight control strategies to favour energy expenditure. Some evidence suggests that exercise might not have the expected impact on energy balance, and may actually cause a decrease in the subsequent physical activity energy expenditure. To question the impact of an acute exercise session of varying intensities on daily energy expenditure in lean and obese adolescents. Data from three separate studies conducted in lean and obese 12-15 years old adolescents (study 1: 12 obese; study 2: 10 obese and nine lean; study 3: 15 obese) have been used. Daily energy expenditure (DEE) was assessed in studies 1 and 2 during an exercise condition with an exercise bout at 70%VO(2max) (EX) and a rest day (REST) (using Actiheart and Armbands, respectively). In study 3, DEE was assessed in calorimetric chambers during (i) a high intensity exercise condition (HIE - 75%VO(2max)) and (ji) a condition with a low intensity exercise (LIE - 40%VO(2max)) and (iii) a rest condition (REST). Morning energy expenditure was significantly higher during the exercise conditions whatever the intensity compared with rest. Afternoon energy expenditure was significantly lower following HIE compared to the rest condition in studies 2 and 3. Afternoon energy expenditure was not significantly different between LIE and REST in study 2. Total DEE was not significantly different between conditions in the three studies. Obese adolescents seem to show a compensatory response to an acute session of HIE (>70%VO(2max)) by decreasing their following physical activity energy expenditure. Although HIE favours body composition, physical fitness and metabolic profile improvements, this induced compensatory energy expenditure response has to be considered to optimize its effect on weight loss.

Association of cardiovascular response to an acute resistance training session with the ACE gene polymorphism in sedentary women: a randomized trial

BackgroundThe aim of the present study was to verify the effects of an acute resistance training (RT) session and insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) on systolic (SBP), diastolic (DBP) and mean blood pressure (MBP), and heart rate (HR).MethodsThe sample consisted of 27 sedentary women (33.3 ± 8.2 yrs; 69.1 ± 13.8 kg; 1.57 ± 0.05 m; 27.6 ± 5.1 kg/m2) divided into two groups according to their polymorphism I/D (DD = 9; II + ID = 18). Volunteers underwent two experimental sessions: RT – an acute session performed with three sets at 60% of one-repetition maximum (1RM) interspersed with 1 minute rest interval between exercises and sets, and a control session (CON) in which they remained seated for 30 minutes in the laboratory. SBP, DBP, MBP and HR were measured before exercise and during one hour every 10 minutes after sessions, in the seated position. A two-way ANOVA for repeated measures with Tukey’s post hoc test was used for the intra and inter-group comparisons.ResultsThere were no statistically significant differences on SBP, DBP and MBP after the experimental protocols, and no effect of ACE polymorphism (P > 0.05). However, comparing CON versus exercise effect size values (ES), homozygotic carriers of the allele D presented a drop in SBP which was considered moderate, while in allele I carriers it was small, 30 minutes after exercise. In MBP, homozygotic D carriers exhibited a large ES 20 minutes post-exercise. HR was higher at 10, 20 and 30 minutes after exercise as compared to pre-exercise only for carriers of the I allele (P < 0.05).ConclusionsTherefore, an acute RT session reduces clinical BP. In addition to this; it seems that ACE polymorphism had some influence on cardiovascular response to exercise.Trial RegistrationRBR-6GDYVZ

Autologous Transplantation for Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia Achieves Outcomes Similar to Allogeneic Transplantation - Results of CALGB 10001 (Alliance)

AbstractAbstract ▪816▪This icon denotes a clinically relevant abstractWe hypothesized that imatinib plus sequential chemotherapy would result in significant leukemia cell cytoreduction (molecular remission) in patients with Ph+ acute lymphoblastic leukemia (ALL), allowing collection of normal hematopoietic stem cells uncontaminated by residual BCR/ABL+ lymphoblasts and thus reduce the likelihood of relapse after autologous (auto) stem cell transplant (SCT) for patients <60 years old without sibling donors. Cancer and Leukemia Group B (CALGB) study 10001 enrolled 58 patients who received 3–4 courses of imatinib (400 mg twice daily) plus sequential chemotherapy followed either by total body irradiation (TBI, 1320 cGy)/etoposide (60 mg/kg) and an allogeneic (allo) SCT from a matched sibling donor or by TBI/etoposide/cyclophosphamide (100 mg/kg) and auto-SCT. Fifteen had an allo-SCT on study using their matched sibling donor; others were transplanted off study using unrelated donors or received alternative therapy. Nineteen have undergone auto-SCT. Imatinib plus chemotherapy resulted in reverse-transcriptase polymerase chain reaction (RT-PCR) negative stem cells (complete molecular response, CMR) in 9 of the 19 patients; 4 remained minimally positive (major molecular response, MMR; <0.001) and 6 were not evaluable. RT-PCR status of the stem cell products had no effect on overall survival (OS) or disease-free survival (DFS) after auto-SCT (CMR vs. MMR P=0.77 for DFS and P=0.50 for OS). We studied the effect of minimal residual disease (MRD) detection on outcome following auto-SCT. At day +120 post auto-SCT, DFS and OS were longer in patients who achieved at least a MMR (n=8) than patients who did not have a MMR (n=6) at that time point (P=0.045 and P=0.011; Panels A and B). After allo-SCT, 7 of 10 patients who survived >120 days had CMR; 2 additional patients achieved MMR, and 1 patient had residual MRD >0.001 (less than MMR); however, the sample size was too small to analyze the effect of MRD on outcome. After a median follow up time of 5.1 years, 9 (47%) of 19 auto-SCT patients and 7 of 15 (47%) of the allo-SCT patients remain alive in continuous CR. Ten of the transplanted patients have relapsed (8 following auto-SCT and 2 following allo-SCT); relapses occurred at a median of 5.9 months following auto-SCT. The DFS (median, 5.5 vs 4.1 years; P=0.84) and OS (median, 6.0 years vs. not reached at >6 years; P=0.90) were similar between those who underwent auto- or allo-SCT (Panels C and D). We conclude that patients who have MRD at levels lower than or equal to MMR following auto-SCT have prolonged survival and that auto-SCT represents a safe and effective alternative to allo-SCT for Ph+ ALL patients without sibling donors. The intergroup trial CALGB 10701 (Alliance) is now testing this strategy in Ph+ ALL patients >50 year old, using dasatinib as the BCR/ABL inhibitor. [Display omitted] Disclosures:Wetzler:BMS: Research Funding; Novartis: Research Funding. Off Label Use: Dasatinib is off label but in a clinical trial. 615A Oral Session 1 (3 abstracts) Acute promyelocytic leukemia 622A Oral Session 1 (3 abstracts) Autologous and Allogeneic Transplantatin CLL - Biology and Pathophysiology, excluding Therapy: Cell Signaling Leukemias - Biology, Cytogenetics and Molecular Markers in Diagnosis and Prognosis: Chronic Lymphoid and Myeloid Leukemias 111. Hemoglobinopathies, excluding Thalassemia IV

Treinamento aeróbio não altera pressão arterial de mulheres menopausadas e com síndrome metabólica

Arterial Hypertension (AH) is an aggravating condition for Metabolic Syndrome (MS), as well as being aggravated by it. Menopause can make hypertension treatment more difficult, as it favors the worsening of MS components. Although there is evidence that exercise training reduces blood pressure, whether menopause and SM affect the exercise-induced benefits is yet to be elucidated. To compare the effects of aerobic training on blood pressure in non-menopausal and menopausal women with MS METHODS: A total of 44 women were recruited and divided into four groups: non-menopausal control (NMC: 39.5 ± 3.6 years, n = 11); menopausal control (MC: 54.9 ± 5.9 years, n = 12), non-menopausal aerobics (NMA: 43.1 ± 6.8 years, n = 11) and menopausal aerobics (MA: 52.1 ± 5 years, n = 10). The exercise groups performed aerobic training for three months, five times a week, at an intensity between 60% and 70% of heart rate reserve. The resting blood pressure and blood pressure response after 60 minutes of exercise were measured before and after the training period. The two-way ANOVA test was used, considering a p value < 0.05. The training program resulted in a decrease in abdominal fat, blood glucose and improved VO2 max. Compared to pre-intervention values, Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) did not change after training in NMC, MC, MA and NMA groups (p > 0.05). Three months of aerobic training improved MS components, but did not alter resting blood pressure or the BP response after an acute exercise session in women with MS.

Acute effects of resistance training on cytokines and osteoprotegerin in women with metabolic syndrome

Chronic inflammation has been identified as an important component of metabolic syndrome (MetS). Inhibition of the inflammatory mediator signals is a promising strategy against insulin resistance, atherosclerosis and other problems associated with MetS. Regular exercise decreases the components associated with MetS, including inflammatory cytokines. However, the relationship between an acute resistance training (RT) session, cytokine levels and MetS is unclear. Therefore, the aim was to evaluate the effects of a single bout of acute RT on tumour necrosis factor (TNF-α), interleukins (IL) IL-1a, IL-1β, IL-12, IL-6, IL-10 and osteoprotegerin (OPG) in women with MetS. Twenty-four women were divided into 2 groups: metabolic syndrome (MetS) and non-metabolic syndrome (Non-MetS). After the familiarization and testing for 1 repetition maximum (1RM), participants completed 3 sets of 10 repetitions in the following exercises: machine leg press, leg extension, leg curl, chest press, lat front pull-down and machine shoulder press with 60% of 1RM followed by 15 repetitions of abdominal crunches. A rest interval of 1min was allowed between sets and exercises. Plasma TNF-α, IL-1a, IL-1β, IL-12, IL-6, IL-10 and OPG were measured before, immediately post and 60min after RT. MetS group showed significantly higher concentrations of IL-1β (P=0·024) and IL-6 (P=0·049) and a trend for higher TNF-α values (P=0·092) compared with Non-MetS. There was no group×time interactions after the RT session on the measured cytokines and osteoprotegerin. In conclusion, acute RT session induced no additional increase in pro-inflammatory cytokines nor a decrease in anti-inflammatory cytokines and OPG in women with MetS.

Acute Effects of Resistance Exercise on 24-h Blood Pressure in Middle Aged Overweight and Obese Women

This investigation was designed to evaluate responses of blood pressure (BP) following an acute resistance exercise (RE) session. Middle-aged women (N=13) who were classified as overweight (N=8) or obese (N=5) according to body mass index (BMI) participated in the investigation. Participants were randomly submitted to a control session (30-min seated rest) and a exercise session (3 sets, 10 repetitions at 60% 1RM of exercises for the upper and lower body) with systolic (SBP), diastolic (DBP) and mean blood pressure (MBP) obtained at rest and 10, 20, 30, 40, 50, and 60-min following exercise, and through 24 h. Acute RE decreased SBP at 10, 30, and 40-min compared with pre-exercise and control (P<0.05). DBP decreased at 10 and 40-min post-exercise compared with the control trial (P<0.05). Both SBP and DBP decreased in the nighttime period (-4.2 mmHg and -4.1 mmHg, respectively) and in the overall 24 h period (-3.6 mmHg and -4.5 mmHg, respectively) following the acute RE session when compared with the control trial. These findings indicate important benefits of acute RE on BP circadian rhythm, particularly at night as well as in the morning, which are critical periods associated with increased risk for cardiovascular events.

Wide-Pulse Electrical Stimulation to an Intrinsic Foot Muscle Induces Acute Functional Changes in Forefoot-Rearfoot Coupling Behaviour during Walking

Interventions for strengthening intrinsic foot muscles may be beneficial for rehabilitation from overuse injuries. In this study the acute effects of high-frequency, low-intensity wide-pulse electrical stimulation (WPS) over an intrinsic muscle on subsequent foot function during walking was assessed in healthy participants. WPS was delivered to the m. abductor hallucis (m.AH) of the non-dominant foot during relaxed standing. 3-dimensional forefoot (FF)--rearfoot (RF) coordination was quantified with a vector coding technique within separate periods of the stance phase to study WPS functional effects on foot motion. 4 types of coordinative strategies between the FF and RF were interpreted and compared PRE-to-POST-WPS for both the experimental and control feet. Bilateral electromyography (EMG) from m.AH was analysed during the intervention period for evidence of acute neuromuscular adaptation. The results showed that WPS significantly modulated FF-RF coordination during mid-stance, indicative of a more stable foot. Specifically, a statistically significant increase in FF eversion with concomitant RF inversion in the frontal plane and RF-dominated adduction in the transverse plane was observed. Subject-specific increases in post-stimulus m.AH EMG activation were observed but this was not reflected in an overall group effect. It is concluded that the structural integrity of the foot during walking is enhanced following an acute session of WPS and that this mechanical effect is most likely due to stimulation induced post-tetanic potentiation of synaptic transmission.

Blood Glucose Control for Individuals with Type-2 Diabetes

This study compared the effects of resistance exercise (RE) intensities on blood glucose (GLUC) of individuals without (ND) and with type-2 diabetes (T2D). Nine individuals with T2D and 10 ND performed: (a) RE circuit at 23% of 1 maximal repetition (1RM) (RE_L); (b) RE circuit at 43% 1RM (RE_M); and (c) control (CON) session. Blood lactate (LAC) and GLUC were measured before, during, and postinterventions. Double product (DP) and rate of perceived exertion (RPE) were recorded. The area under the curve (AUC) revealed the effects of RE circuits in reducing GLUC in individuals with T2D (RE_L: 12,556 ± 3,269 vs. RE_M: 13,433 ± 3,054 vs. CON: 14,576 ± 3,922 mg.dl(-1).145 minutes; p < 0.05) with a lower AUC of GLUC in RE_L in comparison to RE_M. Similarly, for ND the RE_L reduced the AUC of GLUC when compared with RE_M and CON (RE_L: 10,943 ± 956 vs. RE_M: 12,156 ± 1,062 vs. CON: 11,498 ± 882 mg.dl(-1).145 minutes; p < 0.05). The AUC of GLUC was higher for T2D compared with ND on CON condition (p = 0.02). However, after RE circuits the difference between groups for AUC of GLUC was abolished. The RE_M for T2D was more stressful when compared with RE_L for LAC (CON: 1.3 ± 0.5 vs. RE_L: 5.5 ± 1.5 vs. RE_M: 6.8 ± 1.3 mmol·L(-1); p < 0.05), DP (CON: 8,415 ± 1,223 vs. RE_L: 15,980 ± 2,007 vs. RE_M: 18,047 ± 3,693 mmHg.bpm(-1); p < 0.05), and RPE (RE_L: 11 ± 2 vs. RE_M: 13 ± 2 Borg Scale; p < 0.05). We concluded that RE_L and RE_M were effective in reducing GLUC for individuals with T2D, with lower cardiovascular-metabolic and perceptual stress being observed for RE_L. These data suggest that acute RE sessions at light or moderate intensities are effective for controlling GLUC in individuals with T2D.

Regulators of blood lipids and lipoproteins? PPARδ and AMPK, induced by exercise, are correlated with lipids and lipoproteins in overweight/obese men and women

PPARδ is a transcription factor regulating the expression of genes involved in oxidative metabolism, which may regulate blood cholesterols through transcription of oxidative and lipoprotein metabolism genes. To determine the association of skeletal muscle PPARδ content with blood lipids and lipoproteins before and following exercise, overweight and obese men (n = 9) and women (n = 7) were recruited; age, BMI, body fat percentage, and Vo(2max) were (means ± SE) 45 ± 2.5 yr, 31.9 ± 1.4 kg/m(-2), 41.1 ± 1.5%, and 26.0 ± 1.3 mLO(2)·kg(-1)·min(-1), respectively. Subjects performed 12 wk of endurance exercise training (3 sessions/wk, progressing to 500 kcal/session). To assess the acute exercise response, subjects performed a single exercise session on a treadmill (70% Vo(2max), 400 kcal energy expenditure) before and after training. Muscle and blood samples were obtained prior to any exercise and 24 h after each acute exercise session. Muscle was analyzed for protein content of PPARδ, PPARα, PGC-1α, AMPKα, and the oxidative and lipoprotein markers FAT/CD36, CPT I, COX-IV, LPL, F(1) ATPase, ABCAI, and LDL receptor. Blood was assessed for lipids and lipoproteins. Repeated-measures ANOVA revealed no influence of sex on measured outcomes. PPARδ, PGC-1α, FAT/CD36, and LPL content were enhanced following acute exercise, whereas PPARα, AMPKα, CPT I, and COX-IV content were enhanced only after exercise training. PPARδ content negatively correlated with total and LDL cholesterol concentrations primarily in the untrained condition (r ≤ -0.4946, P < 0.05), whereas AMPKα was positively correlated with HDL cholesterol concentrations regardless of exercise (r ≥ 0.5543, P < 0.05). Our findings demonstrate exercise-induced expression of skeletal muscle PPARs and their target proteins, and this expression is associated with improved blood lipids and lipoproteins in obese adults.

Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exercise

Our aim was to examine the effect of betaine supplementation on selected circulating hormonal measures and Akt muscle signaling proteins after an acute exercise session. Twelve trained men (age 19.7 ± 1.23 years) underwent 2 weeks of supplementation with either betaine (B) (1.25 g BID) or placebo (P). Following a 2-week washout period, subjects underwent supplementation with the other treatment (B or P). Before and after each 2-week period, subjects performed an acute exercise session (AES). Circulating GH, IGF-1, cortisol, and insulin were measured. Vastus lateralis samples were analyzed for signaling proteins (Akt, p70 S6k, AMPK). B (vs. P) supplementation approached a significant increase in GH (mean ± SD (Area under the curve, AUC), B: 40.72 ± 6.14, P: 38.28 ± 5.54, p = 0.060) and significantly increased IGF-1 (mean ± SD (AUC), B: 106.19 ± 13.45, P: 95.10 ± 14.23, p = 0.010), but significantly decreased cortisol (mean ± SD (AUC), B: 1,079.18 ± 110.02, P: 1,228.53 ± 130.32, p = 0.007). There was no difference in insulin (AUC). B increased resting Total muscle Akt (p = 0.003). B potentiated phosphorylation (relative to P) of Akt (Ser(473)) and p70 S6 k (Thr(389)) (p = 0.016 and p = 0.005, respectively). Phosphorylation of AMPK (Thr(172)) decreased during both treatments (both p = 0.001). Betaine (vs. placebo) supplementation enhanced both the anabolic endocrine profile and the corresponding anabolic signaling environment, suggesting increased protein synthesis.

GH and Cortisol Responses Following an Acute Session of Respiratory Muscle Endurance Training in Severely Obese Patients

It is well established that obese patients are hypo-responsive to classical GH-releasing stimuli, including aerobic exercise. Recently, we have demonstrated that whole body vibration was able to markedly stimulate GH secretion in obese patients, thus suggesting that this refractoriness is not absolute but dependent on the GH-releasing stimulus. Furthermore, we have shown the ability of a respiratory muscle endurance training (RMET) to stimulate GH and cortisol secretion in healthy subjects. The objective of this study was to evaluate the effects of RMET on GH and cortisol responses in severely obese patients. Eight severely obese patients (4 M/4 F, mean age±SEM: 22.8±1.6 years, body mass index, BMI: 39.9±1.1 kg/m2) underwent an incremental progressive RMET protocol of 11 daily sessions, obtained through the use of a specifically designed respiratory device (Spiro Tiger®). The 12th session of RMET (15 min duration: 1 min at a respiration rate of 28 acts/min, 5 min at 32 acts/min, 5 min at 34 acts/min, 4 min at 36 acts/min) was associated with blood samplings for determination of GH, cortisol, and lactate (LA) levels. An age- and sex-matched normal-weighted control group (n=7, 4 M/3 F, age: 26.1±3.1 years, BMI: 22.4±0.6 kg/m2) was also recruited. In both normal-weighted subjects and obese patients, GH secretion significantly increased after a 15-min RMET session. Although serum GH levels at 30 min were higher in normal-weighted subjects than in obese patients, there was no statistically significant difference in either GH peaks or net GH areas under the curve between the 2 groups. RMET significantly increased serum cortisol levels in normal-weighted subjects, but was associated to a progressive cortisol decline in obese patients. RMET stimulated LA production, with no significant differences in normal-weighted subjects and in obese patients. A 15-min RMET session was capable to induce a GH response in severely obese patients, which was comparable to that recorded in normal-weighted subjects. A progressive decline in serum cortisol levels occurred in obese patients after RMET, while an opposite pattern (i. e., a significant cortisol increase) was found in normal-weighted subjects. Optimization of long-term RMET protocols could represent a valid strategy to (physiologically) stimulate GH/IGF-I system in those GH hyposecretory states such as obesity.

Conducting an Acute Intense Interval Exercise Session During the Ramadan Fasting Month: What Is the Optimal Time of the Day?

This study examines the effects of Ramadan fasting on performance during an intense exercise session performed at three different times of the day, i.e., 08:00, 18:00, and 21:00 h. The purpose was to determine the optimal time of the day to perform an acute high-intensity interval exercise during the Ramadan fasting month. After familiarization, nine trained athletes performed six 30-s Wingate anaerobic test (WAnT) cycle bouts followed by a time-to-exhaustion (Texh) cycle on six separate randomized and counterbalanced occasions. The three time-of-day nonfasting (control, CON) exercise sessions were performed before the Ramadan month, and the three corresponding time-of-day Ramadan fasting (RAM) exercise sessions were performed during the Ramadan month. Note that the 21:00 h session during Ramadan month was conducted in the nonfasted state after the breaking of the day's fast. Total work (TW) completed during the six WAnT bouts was significantly lower during RAM compared to CON for the 08:00 and 18:00 h (p < .017; effect size [d] = .55 [small] and .39 [small], respectively) sessions, but not for the 21:00 h (p = .03, d = .18 [trivial]) session. The Texh cycle duration was significantly shorter during RAM than CON in the 18:00 (p < .017, d = .93 [moderate]) session, but not in the 08:00 (p = .03, d = .57 [small]) and 21:00 h (p = .96, d = .02 [trivial]) sessions. In conclusion, Ramadan fasting had a small to moderate, negative impact on quality of performance during an acute high-intensity exercise session, particularly during the period of the daytime fast. The optimal time to conduct an acute high-intensity exercise session during the Ramadan fasting month is in the evening, after the breaking of the day's fast. (Author correspondence: abdul_rashid_aziz@ssc.gov.sg)

Acute Exercise and Training Alter Blood Lipid and Lipoprotein Profiles Differently in Overweight and Obese Men and Women

Our purpose was to elucidate effects of acute exercise and training on blood lipids-lipoproteins, and high-sensitivity C-reactive protein (hsCRP) in overweight/obese men (n = 10) and women (n = 8); age, BMI, body fat percentage, and VO(2)max were (mean ± SEM): 45 ± 2.5 years, 31.9 ± 1.4 kg·m(-2), 41.1 ± 1.5%, and 25.2 ± 1.3 mlO(2)·kg(-1)·min(-1). Before exercise training subjects performed an acute exercise session on a treadmill (70% VO(2)max, 400 kcal energy expenditure), followed by 12 weeks of endurance exercise training (land-based or aquatic-based treadmill): 3 sessions·week(-1), progressing to 500 kcal·session(-1) during which subjects maintained accustomed dietary habits. After training, the acute exercise session was repeated. Blood samples, obtained immediately before and 24 h after acute exercise sessions, were analyzed for serum lipids, lipoproteins, and hsCRP adjusted for plasma volume shifts. Exercise training increased VO(2)max (+3.67 mlO(2)·kg(-1)·min(-1), P < 0.001) and reduced body weight (-2.7 kg, P < 0.01). Training increased high-density lipoprotein (HDL) and HDL(2b)-cholesterol (HDL-C) concentrations (+3.7 and +2.4 mg·dl(-1), P < 0.05) and particle numbers (+588 and +206 nmol·l(-1), P < 0.05) in men. In women despite no change in total HDL-C, subfractions shifted from HDL(3)-C (-3.2, P < 0.01) to HDL(2b)-C (+3.5, P < 0.05) and HDL(2a)-C (+2.2 mg·dl(-1), P < 0.05), with increased HDL(2b) particle number (+313 nmol·l(-1), P < 0.05). Training reduced LDL(3) concentration and particle number in women (-1.6 mg·dl(-1) and -16 nmol·l(-1), P < 0.05). Acute exercise reduced the total cholesterol (TC): HDL-C ratio in men (-0.16, P < 0.01) and increased hsCRP in all subjects (+0.05 mg·dl(-1), P < 0.05), regardless of training. Training did not affect acute exercise responses. Our data support the efficacy of endurance training, without dietary intervention, to elicit beneficial changes in blood lipids-lipoproteins in obese men and women.

Análisis electromiográfico del efecto de relajación en el bíceps femoral en sujetos sometidos a estiramientos vs. facilitación neuromuscular propioceptiva

ObjectiveTo assess the level of relaxation of the biceps femoris in individuals carrying out an acute session of stretching and proprioceptive neuromuscular facilitation. Material and methodsThe subjects were randomly divided into: a) group of proprioceptive neuromuscular facilitation (GFNP n=15; 22.13±2.70 years, BMI 24.12±3.69) who performed the contraction-relaxation technique; b) stretching group (SG, n=15; 22.87±04.07 years; BMI 24.51±4.33) who performed submaximal stretch held for 6seconds. These stretches were performed with the hip flexed and knee extended, c) control group (CG n=15; 24.67±4.30 years, BMI 23.91±3.09). Electromyographic analysis was performed pre and post intervention. ResultsA repeated measures ANOVA revealed that there was a significant reduction in muscle activity GFNP (Δ %=–46.95%, P=.0001) and GA (Δ %=–30.71%, P=.034). The results for the GC did not reveal any significant difference. The intergroup comparison revealed that the GFNP had significantly lower values than the GC in the post-test (Δ %=–41.57%, P=.004), no significant differences being found. ConclusionsBoth flexibility training methods studied cause similar effects on relaxation in the analyzed muscle (biceps femoris), although the GFNP group was the only one that showed a significant difference compared to the control group.

The Acute Effects of Yoga on Executive Function

Despite an increase in the prevalence of yoga exercise, research focusing on the relationship between yoga exercise and cognition is limited. The purpose of this study was to examine the effects of an acute yoga exercise session, relative to aerobic exercise, on cognitive performance. A repeated measures design was employed where 30 female college-aged participants (Mean age = 20.07, SD = 1.95) completed 3 counterbalanced testing sessions: a yoga exercise session, an aerobic exercise session, and a baseline assessment. The flanker and n-back tasks were used to measure cognitive performance. Results showed that cognitive performance after the yoga exercise bout was significantly superior (ie, shorter reaction times, increased accuracy) as compared with the aerobic and baseline conditions for both inhibition and working memory tasks. The aerobic and baseline performance was not significantly different, contradicting some of the previous findings in the acute aerobic exercise and cognition literature. These findings are discussed relative to the need to explore the effects of other nontraditional modes of exercise such as yoga on cognition and the importance of time elapsed between the cessation of the exercise bout and the initiation of cognitive assessments in improving task performance.

Physical exercise and pancreatic islets

Diabetes mellitus (DM) is a great public health problem, which attacks part of the world population, being characterized by an imbalance in body glucose homeostasis. Physical exercise is pointed as a protective agent and is also recommended to people with DM. As pancreatic islets present an important role in glucose homeostasis, we aim to study the role of physical exercise (chronic adaptations and acute responses) in pancreatic islets functionality in Wistar male rats. First, animals were divided into two groups: sedentary (S) and aerobic trained (T). At the end of 8 weeks, half of them (S and T) were submitted to an acute exercise session (exercise until exhaustion), being subdivided as acute sedentary (AS) and acute trained (AT). After the experimental period, periepididymal, retroperitoneal and subcutaneous fat pads, blood, soleus muscle and pancreatic islets were collected and prepared for further analysis. From the pancreatic islets, total insulin content, insulin secretion stimulated by glucose, leucine, arginine and carbachol were analyzed. Our results pointed that body adiposity and glucose homeostasis improved with chronic physical exercise. In addition, total insulin content was reduced in group AT, insulin secretion stimulated by glucose was reduced in trained groups (T and AT) and insulin secretion stimulated by carbachol was increased in group AT. There were no significant differences in insulin secretion stimulated by arginine and leucine. We identified a possible modulating action on insulin secretion, probably related to the association of chronic adaptation with an acute response on cholinergic activity in pancreatic islets.

P01.19. Oxytocin Receptor Gene (OXTR) variation is associated with enhanced affective and placebo conditioning to touch-based complementary interventions

Purpose Patients often report reductions in negative affect in response to biofield and touch interventions. While reasons for improvement remain unclear, current theory and evidence suggest the need to examine oxytocin as well as placebo mechanisms. We investigated changes in negative affect (NA) during an acute session of verum or touch-based healing, and related NA changes to placebo elements, plasma oxytocin changes, and the oxytocin receptor (OXTR SNP rs53576) polymorphism (which has been associated with psychological sensitivity to social context).

The magnitude and duration of post-exercise hypotension after land and water exercises

The objective of the study was to determine and compare the magnitude and duration of post-exercise hypotension (PEH) during free-living conditions after an acute session of concurrent water and land exercise in individuals with prehypertension and hypertension. Twenty-one men and women (aged 52±10years) volunteered for the study. Participants completed a no exercise control session, a water exercise session and a land exercise session in random order. After all three sessions, participants underwent 24-h monitoring using an Ergoscan ambulatory BP monitoring device. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored to determine changes from resting values after each session and to compare the PEH responses between land and water exercises. During daytime, both land and water exercises resulted in significantly lower SBP (12.7 and 11.3mmHg) compared to the control session (2.3mmHg). The PEH response lasted for 24h after land exercise and 9h after water exercise. There was no difference in the daytime DBP for the three treatments (P>0.05). Although all three groups showed significant reductions during nighttime, both exercise treatments showed greater nocturnal falls in BP than the control treatment. This is the first study to show that the magnitude of the PEH response is similar for land and water exercises, although the duration of PEH may be longer for land exercise. These results suggest that water exercise is a safe alternative exercise modality for individuals with suspected and known hypertension.

Effects of daily levels of fatigue and acutely induced fatigue on the visual evoked magnetic response

Fatigue is a common complaint in modern society. As photosensitivity is associated with fatigue, this study aimed to clarify the relationship between neural response to visual stimuli and fatigue using a 160-channel whole-head-type magnetoencephalographic system. Twelve healthy male volunteers were enrolled. Participants were randomly assigned to two groups in a single-blinded, crossover fashion to perform acute fatigue-inducing mental task sessions, i.e., 0-back or 2-back test for 30min. Visual evoked magnetic field (VEF) intensities were evaluated by standardized low-resolution brain electromagnetic tomography modified for a quantifiable method. VEF consisted of two phases, and although acute fatigue did not alter the VEF intensities and the intensities before the acute fatigue-inducing mental task sessions were not correlated with the Chalder's Fatigue Scale scores in either of the two phases, the intensities after the 0-back test trials for 30min in Phase 1 and those after the 2-back test trials in Phase 2 were significantly correlated with the fatigue scale scores. The daily level of fatigue was related to VEF intensity after the acute mental fatigue loads. Our findings provide new perspectives to evaluate our daily level of fatigue as well as to clarify the neural mechanisms underlying it.

Electrode configuration influences electrically evoked compound action potentials of guinea pig

The intracochlear electrode array of cochlear implants is used to electrically stimulate the residual hearing auditory nerve of profound sensorineural hearing loss. The present products used to implant possess configuration with the different contact style and different separation between the contacts. This study investigated the effects of electrode configuration on the auditory nerve compound action potentials in response to electric stimulation. We also investigated the channel interaction of the different electrode configuration. Adult guinea pigs were used in acute experimental sessions. We implanted three kinds of electrode array either (1) a narrow spacing banded array consisting of a tapered silicone elastomer carrier with a linear series of banding contacts; or (2) two wider spacing arrays consisting of a tapered silicone elastomer carrier with oval-shaped contacts. The electrically evoked compound action potential (ECAP) was recorded from the intracochlear. ECAP latency functions indicated that the electrode array with narrow spacing and banded contacts generated shorter latency than the electrode array with wider spacing and oval-shaped contacts. We also observed that the electrode array with banded contacts had greater ECAP amplitude than the electrode with oval-shaped contacts.