Submaximal Aerobic Exercise Research Articles

The Impact of Sub-maximal Exercise on Neuropathic Pain, Inflammation, and Affect Among Adults With Spinal Cord Injury: A Pilot Study.

Introduction: Persons with spinal cord injury (SCI) often report high levels of neuropathic pain (NP) and poor well-being, which may result from increased inflammation. This study examined the impact of sub-maximal aerobic exercise on NP, inflammation and psychological affect among adults with SCI.Methods: Eight active adults with tetraplegia (n-4, AIS A-C) and paraplegia (n = 4, AIS A-C) performed 30-min of arm-crank aerobic exercise and reported their ratings of perceived exertion (RPE) each minute. Measures of NP, affect, and inflammatory cytokines (IL-6, IL-10, IL-1ra, TNF-α) were taken pre-(T0), immediately post-(T1), and 90-min post-exercise (T2).Results: NP decreased between T0 and T1 for tetraplegics (−60%, d = 0.47; CI = −0.32, 2.02) and paraplegics (−16%, d = 0.15; CI = −0.30, 0.90). Correlations between change in cytokines and change in NP were medium-to large for tetraplegics (rs ranged from −0.820 to 0.965) and paraplegics (rs ranged from −0.598 to 0.833). However, the pattern of correlations between change in cytokines and affect was inconsistent between groups. Lower baseline levels of IL-1ra predicted greater decreases in NP immediately post-exercise (r = 0.83, p = 0.01).Conclusion: Sub-maximal exercise can positively impact NP for some persons with SCI. Further experimental research should identify the optimal exercise intensity to reduce NP for persons with SCI, in addition to understanding biomarkers which may predict changes in NP.Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03955523.

Sub-maximal aerobic exercise training reduces haematocrit and ameliorates symptoms in Andean highlanders with chronic mountain sickness.

New Findings What is the central question of this study? What is the effect of sub‐maximal aerobic exercise training on signs and symptoms of chronic mountain sickness (CMS) in Andean highlanders? What is the main finding and its importance? Aerobic exercise training (ET) effectively reduces haematocrit, ameliorates symptoms and improves aerobic capacity in CMS patients, suggesting that a regular aerobic ET programme might be used as a low‐cost non‐invasive/non‐pharmacological management strategy of this syndrome. Excessive erythrocytosis is the hallmark sign of chronic mountain sickness (CMS), a debilitating syndrome associated with neurological symptoms and increased cardiovascular risk. We have shown that unlike sedentary residents at the same altitude, trained individuals maintain haematocrit within sea‐level range, and thus we hypothesise that aerobic exercise training (ET) might reduce excessive haematocrit and ameliorate CMS signs and symptoms. Eight highlander men (38 ± 12 years) with CMS (haematocrit: 70.6 ± 1.9%, CMS score: 8.8 ± 1.4) from Cerro de Pasco, Peru (4340 m) participated in the study. Baseline assessment included haematocrit, CMS score, pulse oximetry, maximal cardiopulmonary exercise testing and in‐office plus 24 h ambulatory blood pressure (BP) monitoring. Blood samples were collected to assess cardiometabolic, erythropoietic, and haemolysis markers. ET consisted of pedalling exercise in a cycloergometer at 60% of V˙O2peak for 1 h/day, 4 days/week for 8 weeks, and participants were assessed at weeks 4 and 8. Haematocrit and CMS score decreased significantly by week 8 (to 65.6 ± 6.6%, and 3.5 ± 0.8, respectively, P < 0.05), while V˙O2peak and maximum workload increased with ET (33.8 ± 2.4 vs. 37.2 ± 2.0 ml/min/kg, P < 0.05; and 172.5 ± 9.4 vs. 210.0 ± 27.8 W, P < 0.01; respectively). Except for an increase in high‐density lipoprotein cholesterol, other blood markers and BP showed no differences. Our results suggest that reduction of haematocrit and CMS symptoms results mainly from haemodilution due to plasma volume expansion rather than to haemolysis. In conclusion, we show that ET can effectively reduce haematocrit, ameliorate symptoms and improve aerobic capacity in CMS patients, suggesting that regular aerobic exercise might be used as a low‐cost non‐invasive and non‐pharmacological management strategy.

Concussion History and Heart Rate Variability During Bouts of Acute Stress.

After a sport-related concussion, many athletes experience persisting neurophysiological alterations. These alterations may be absent at rest but emerge during moments of physiological stress. Unnoticed and untreated neurophysiological dysfunction may negatively affect long-term neurologic health in adolescent athletes, as they are at a critical point in development. To assess cardio-autonomic functioning in athletes with and those without a history of concussion by quantifying measures of heart rate variability (HRV) during times of physical and mental exertion. Case-control study. Research laboratory. Thirty-four male Hockey Quebec Midget-AAA hockey players were separated into those with (n = 16; age = 16.06 ± 0.73 years, body mass index = 23.29 ± 1.79) and those without (n = 18; age = 15.98 ± 0.62 years, body mass index = 23.60 ± 2.49) a history of concussion. All athletes underwent a series of HRV recording sessions (1) at rest, (2) while completing a cognitive task at rest, and (3) while completing a cognitive task after a bout of submaximal aerobic exercise. Time-domain measures of HRV, including mean NN intervals, SD of NN intervals, and root mean square of successive NN interval differences, were quantified for each assessment. No differences in characteristics were evident between groups. No between-groups differences in HRV at rest were observed. However, during the cognitive task at rest and after aerobic exercise, athletes with a history of concussion demonstrated a higher SD of NN intervals (78.1 ± 4.3 versus 63.2 ± 4.1 milliseconds and 71.2 ± 4.3 versus 65.2 ± 3.8 milliseconds, respectively; F1,31 = 4.31, P = .046) and root mean square of successive NN interval differences (75.8 ± 6.0 versus 59.0 ± 5.6 milliseconds and 74.0 ± 5.5 versus 59.0 ± 5.2 milliseconds, respectively; F1,31 = 4.88, P = .04) than athletes without a history of concussion. Concussive injuries may result in long-term cardio-autonomic dysfunction. These deficits may not be present at rest but may be triggered by physiological stress.

The Effect of Submaximal Exercise Followed by Short-Term Cold-Water Immersion on the Inflammatory State in Healthy Recreational Athletes: A Cross-Over Study.

Cold-water immersion (CWI) after exercise is a method used by sportsmen to improve recovery. The aim of the study was to assess the effect of a 3 min CWI on the inflammatory state by measuring levels of interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor α (TNF-α), and transforming growth factor β1 (TGF-β1), and activities of α1-antitrypsin (AAT) and lysosomal enzymes, including arylsulfatase (ASA), acid phosphatase (AcP), and cathepsin D (CTS D), in the blood of healthy recreational athletes. Male volunteers (n = 22, age 25 ± 4.8 yr) performed a 30 min submaximal aerobic exercise, followed by a 20 min rest at room temperature (RT-REST) or a 20 min rest at room temperature with an initial 3 min 8 °C water bath (CWI-REST). Blood samples were taken at baseline, immediately after exercise, and after 20 min of recovery. The IL-6, IL-10, and TNF-α levels and the AAT activity increased significantly immediately after exercise. The IL-6 level was significantly higher after CWI-REST than after RT-REST. No changes in the activities of the lysosomal enzymes were observed. The effect of a 3 min CWI on the level of inflammatory markers during post-exercise recovery was limited. Thus, it might be considered as a widely available method of regeneration for recreational athletes.

EFFECT OF THREE MINUTE STEP TEST ON COGNITION AMONG MEDICAL STUDENTS

Background: Regular physical exercise is linked to produce beneficial influence on cognitive functions. Cognition can be evaluated by Stroop test where a person's selective attention capacity, skills and processing speed are assessed. Limited work has been done to explore the acute effect of exercise on cognition. Objective: To assess whether acute exposure to submaximal aerobic exercise of three minutes can bring changes in the cognitive function (selective attention and cognitive processing ability). The secondary objective was to assess the physical fitness index of medical students. Methods: Twenty four apparently healthy third year male medical students of BPKIHS (B. P. Koirala Institute of Health Sciences) having mean age of 22.33 ± 1.09 years, body height and weight of 170.10 ± 5.85 cm of 65.38 ± 8.84 kg respectively were recruited. A computer based online version of Stroop Test was done to identify cognitive performance in resting sitting position. Then participants were asked to perform 3 min step test. A recovery time of 5 min was given post exercise and Stroop Test was assessed again. Statistical analysis was done using Paired T test. Data are expressed in mean and SD. Level of significance is considered at p&lt;0.05. Results: The reaction time to Stroop Test was significantly reduced after acute physical exercise (before exercise (43.37 ± 7.7s) vs after exercise (36.14 ± 3.6s), p = 0.001). However, no significant difference in the number of correct response to Stroop Test before (19.71 ± 1.08) and after (19.79 ± 0.51) the acute exercise (p=0.575) was observed. Conclusion: Acute bout of aerobic physical exercise improves attention and execution aspects of cognitive function as measured by Stroop Test in young medical students.

Endurance exercise improves avoidance learning and spatial memory, through changes in genes of GABA and relaxin-3, in rats

Different exercise patterns, neurotransmitters, and some genes have numerous effects on learning and memory. This research aims to investigate the long-term effects of submaximal aerobic exercise on spatial memory (SM), passive avoidance learning (PAL), levels of serum relaxin-3, gamma-aminobutyric acid (GABA), RLN3 gene, and glutamic acid decarboxylase (GAD65/67 genes) in the brainstem of adult male Wistar rats. Fifty male Wistar rats were randomly divided into five groups: aerobic exercise groups, performed on a treadmill running (TR), for 5 weeks (Ex5, n = 10), 10 weeks (Ex10, n = 10), involuntary running wheel group for 5 weeks (IRW5, n = 10), sham (Sh, n = 10) and control (Co, n = 10). Consequently, SM, PAL, serum relaxin-3, GABA, and GAD65/67 and RLN3 genes were measured by ELISA and PCR. Ex5, Ex10 and IRW5 improved significantly SM (p ≤ 0.05), PAL (p ≤ 0.001) and decreased significantly relaxin-3 (p ≤ 0.001). RLN3 in the brain also decreased. However, it was not significant. GABA and GAD65/GAD67 increased significantly (p ≤ 0.05) in Ex5, Ex10 compared to Sh and Co. Aerobic exercise enhanced SM and PAL in Ex compared to Co and Sh. However, duration and type of exercise affected the level of enhancement. The serum relaxin-3 and RLN3 gene displayed reverse functions compared to GABA and GAD65/67 genes in Ex. Therefore, the changes of neurotransmitters in serum relaxin-3, GABA, and their genes: RLN3 and GAD65/67 respectively, influenced learning and memory meaningfully.

Effectiveness of Eight Weeks Aerobic and Aerobic-resistance Cardiac Rehabilitation Exercise Training on Hemorheologic Variables among Middle-aged Men with Coronary Artery Disease

Introduction: Hemorheologic disorders are the most important causes of impaired circulation and cardiovascular events. It is also documented that regular and continuous exercise training could improve vascular adaptation to exercise and provide protection against major cardiovascular events. The aim of this study was to evaluate effectiveness of eight-week cardiac rehabilitation exercise by aerobic and aerobic-resistance methods on hemorheologic variables among middle-aged men with coronary artery disease (CAD). Materials and Methods: The present quasi-experimental study was carried out on 51 middle-aged men with CAD aged 45-65 years. Participants were randomly divided into three groups including aerobic exercise, aerobic-resistance exercise, and control group. The experimental groups performed sub-maximal aerobic exercises for eight weeks. Exercise protocol consisted rehabilitation exercises for three sessions a week. In addition to aerobic exercise, aerobic-resistance group received two sessions of resistance exercise using free weights per week for 15 minutes. Results: There was a significant improvement in all hemorheologic variables including fibrinogen concentration (P=0.001), hematocrit concentration (P=0.002), and erythrocyte sedimentation rate (P=0.001) in both aerobic and aerobic-resistance exercise groups compared to the control group. There was also a significant decrease of mentioned hemorheologic variables in aerobic-resistance group compared to aerobic group. Conclusion: Our study showed that eight-week cardiac rehabilitation exercises, especially aerobic-resistance exercise training, could improve the blood hematologic variables in middle-aged men with CAD.

Metabolic Differences During Submaximal, Steady-State Aerobic Exercise between Sarcopenic and Non-Sarcopenic Older Adults

Abstract Objectives To examine differences in metabolic flexibility during submaximal aerobic exercise in sarcopenic (S) and non-sarcopenic (NS) older adults. Methods Twenty-two older adults (mean age ± SE = 77 ± 2) were categorized as NS (n = 11) and S (n = 11) based on grip strength and muscle mass. Participants completed an aerobic, steady-state 10-min walk on a treadmill at 50 – 60% of their estimated V̇O2 max. Indirect calorimetry was assessed at baseline (fasted) and during the treadmill test to analyze respiratory quotient (RQ), carbohydrate (CHO) oxidation and fat oxidation, and % contributions of CHO and fat oxidation to energy expenditure (%CHO and %FAT, respectively). Two-way mixed factorial ANOVAS (time x group) and follow up t-tests were used to examine between group differences. Results At baseline, RQ was higher (0.76 ± 0.01 vs. 0.72 ± 0.01, p = 0.025) and fat oxidation was lower (0.08 ± 0.01 vs. 0.11 ± 0.01 g · min−1, p = 0.003) in S than NS individuals. The S group had significantly greater %CHO versus %FAT from 6 – 10 min of exercise (p = 0.005–0.014), whereas NS individuals maintained an approximately equal distribution of %CHO and %FAT until 8 – 10 min (p = 0.034–0.047). RQ (0.90 ± 0.06 vs. 0.86 ± 0.01, p = 0.039) and %CHO (70% vs. 57%, p = 0.046) were greater in S compared to NS at 8 min of exercise. Fat oxidation was consistently higher in NS than S individuals from 4 - 10 of min exercise (p = 0.016–0.045). Conclusions Since skeletal muscle utilizes a large amount of energy during exercise, metabolic flexibility is key to efficiently utilize both CHO and fat sources to generate energy to match metabolic demands. Our data reveals that NS individuals were able to rely on both fuel sources during submaximal exercise indicating metabolic flexibility. Typically, exercising at 50 – 60% V̇O2 max utilizes 50% CHO and 50% fat contributions to energy expenditure, as observed in NS individuals. On the other hand, in S individuals, CHO composed a much larger proportion of total energy usage during exercise. These findings suggest that S individuals have low metabolic flexibility with higher dependence on CHO for energy during low-moderate aerobic activity. Funding Sources This study was funded by Abbott Nutrition.

Metabolic Health Monitoring By Continuous Sensing of Breath Acetone at ppb

Introduction A major and largely underestimated [1] concern of today’s society is metabolic health (e.g. obesity) that is related to several diseases (e.g., diabetes, cardiovascular illnesses). Various diet strategies (e.g., ketogenic [2], intermittent fasting [3]) as well as exercising are explored but the assessment of treatment effectiveness on an individual level remains difficult. Desired are simple and accurate integrated devices that communicate wirelessly [4] and monitor metabolic changes conveniently at the point-of-care. This is possible through non-invasive acetone detection, a metabolic breath marker of lipolysis [5]. In specific, acetone is formed during hepatic β-oxidation of fatty acids that further divide into acetoacetate [6] that undergoes decarboxylation and enzymatic degradation to acetone [6], which is highly volatile and measureable in exhaled breath [7]. This has led to the development of several acetone sensors in the last decade.Most, however, suffer from cross-interference to endogenous (e.g., isoprene) and background interferants (e.g., alcohol from disinfectants) [8], and their evaluation in the application has been hardly considered, a general challenge in sensor science [9]. Catalytic filters [10] offer a simple and most effective approach to enhance selectivity and continuously mitigate the interference of confounders. Here, we present a low-cost and compact detector based on a flame-made Pt-loaded Al2O3 catalytic filter [11] coupled to a Si/WO3 sensor [8] for rapid and highly selective acetone detection. We apply it for breath analysis to monitor exercising and fasting. Method Nine volunteers attended two separate appointments. In the first, they performed an exhaustive spiroergometry test for determination of the cardiorespiratory fitness, maximum oxygen uptake (VO2) and second ventilatory threshold (VT2). During the second appointment, all volunteers performed a cardiorespiratory fitness-adapted submaximal aerobic exercise protocol [12]. The protocol started at 20% of the individual VT2 (determined in the first appointment) and increased by 10% every 5 min. Breath was sampled every 5 min during exercise, as well as every 30 min during 3 hours of post-exercise rest with an end-tidal breath sampler [13] and analyzed by PTR-ToF-MS and with and without a Pt/Al2O3 filter-enhanced Si/WO3 sensor. Results and Conclusions Figure 1 shows the normalized (i.e., to the baseline at t = 0) end-tidal acetone concentrations during exercising (0 ≤ t < 60 min) and fasting (60 < t ≤ 240 min) for all nine volunteers, as determined with bench-top PTR-ToF-MS (circles) and the Pt/Al2O3 filter-enhanced Si/WO3 sensor (triangles). The error bars indicate the standard error of the mean (SEM) for all volunteers. Baseline acetone concentrations (0.4 - 1.7 ppm) increase marginally during the exercise phase (i.e., < 5%). In contrast, a strong increase (up to 124%) takes place during subsequent fasting. This indicates that the exercise stimulated the body fat metabolism.The impact of the filter is shown best when monitoring breath acetone in situ during exercising. In fact, the sensor with filter follows closely the bench-top PTR-ToF-MS, while the sensor alone deviates (Figure 1a, squares). This might be related to endogenous isoprene (Figure 1b, diamonds), that spikes immediately in breath during muscle activity (up to 656 ppb within the first 5 min [14]) and then declines. While the sensor responds to isoprene [8], this is mitigated by the filter (triangles). Also varying background ethanol (stars) from hand disinfection [15] may affect the sensor. Thus, with filter, this detector is promising for robust and in situ metabolic monitoring to guide personalized dieting and exercising.

The effect of supervised dynamic exercise program on somatosensory temporal discrimination in patients with fibromyalgia syndrome.

Objectives This study aims to investigate the effect of a supervised dynamic exercise program on somatosensory temporal discrimination (STD) which indicates the central sensory processing ability.Patients and methods Forty-eight patients (mean age: 43 years; range, 19 to 64 years) with fibromyalgia syndrome (FMS) were included in this prospective, randomized study between April 2018 and October 2018. Demographics and clinical measurements were recorded. The STD threshold was measured by a researcher blinded to the treatment groups. After baseline assessments, the patients were randomized into two groups: the supervised exercise group (SEG) and the home exercise group (HEG) as the control group. The SEG performed submaximal aerobic exercise and low-medium resistant isotonic exercises under the supervision of a physiotherapist, 1-h per day, three days in a week for four weeks. The HEG was given a home-based exercise program consisting of low-to-medium resistance isotonic exercises and aerobic exercises 1-h per day, three days in a week for four weeks. After exercise program, clinical assessments and STD threshold measurement were repeated.Results Clinical and STD threshold measures improved significantly after four-week exercise program in both groups. The improvements in clinical measures were significantly higher in the SEG. However, there was no difference in the STD threshold improvement between the groups. No correlation was found between the STD threshold measure and clinical features in any patients.Conclusion Although a significant improvement was achieved in impaired STD threshold with SEG, it was not found to be superior to the amelioration observed with HEG.

Can HRV Biofeedback Improve Short-Term Effort Recovery? Implications for Intermittent Load Sports

As intensity and physical demands continue to rise in sport competition, faster and better recovery becomes essential. The aim of this study was to assess the effects of HRV biofeedback (HRVB) while recovering from a submaximal aerobic exercise. Ten physically-active graduate students participated in the study, which was conducted in four sessions: exercise with free-breathing recovery, first resonance frequency (RF) detection, second RF detection, and exercise applying HRVB during recovery. Measurements included time spent running and recovering, HRV parameters, and recovery/exertion perceptions. The results indicate that using HRVB during recovery improves cardiac variability (RRmean, SDNN, RMSSD and LF; p < 0.01). HRVB also lowers recovery time (p < 0.05) and seems to be improving the perception of recovery (p = 0.087). Moreover, time spent exercising (p < 0.01) and perceived physical exertion (p < 0.05) were higher when applying HRVB. The improvement in the psychophysiological adaptation after intensive aerobic exercise provided by the HRVB is a valuable benefit, not only for competition-driven athletes, but also for the general population.

The impact of a 6 week walking intervention on an obese population in relation to walking distance, waist to height ratio and body mass index

Obesity is a health condition, often resulting from an imbalance between physical activity and calorie intake and while invasive and intense interventions may be necessary for some obese individuals (OI), changes in activity and lifestyle over long periods of time are arguably the safest, most sustainable solution. High Intensity Interval Training (HIIT) has been widely observed to increase rapid fat oxidation in obese populations (OPs), it conversely increases health risks for OIs who often have limited cardiovascular fitness, increased joint loading and high blood pressure. However, submaximal aerobic exercise, such as walking, can be used as an initial intervention for OI who lead sedentary lifestyles, to reduce weight and increase aerobic capacity in an arguably safer way. Therefore, the aim of this study was to investigate the effect that a submaximal walking intervention has on anthropometric measures in an OP

Time Course and Magnitude of Tolerance to the Ergogenic Effect of Caffeine on the Second Ventilatory Threshold.

Pre-exercise caffeine ingestion has been shown to increase the workload at ventilatory threshold, suggesting an ergogenic effect of this stimulant on submaximal aerobic exercise. However, the time course of tolerance to the effect of caffeine on ventilatory threshold is unknown. This study aimed to determine the evolution of tolerance to the ergogenic effect of caffeine on the ventilatory threshold. Methods: Eleven participants (age 32.3 ± 4.9 yrs, height 171 ± 8 cm, body mass 66.6 ± 13.6 kg, VO2max = 48.0 ± 3.8 mL/kg/min) took part in a longitudinal, double-blind, placebo-controlled, randomized, crossover experimental design. Each participant took part in two identical treatments: in one treatment, participants ingested a capsule containing 3 mg of caffeine per kg of body mass per day (mg/kg/day) for twenty consecutive days; in the other treatment, participants ingested a capsule filled with a placebo for the same duration and frequency. During these treatments, participants performed a maximal ramp test on a cycle ergometer three times per week and the second ventilatory threshold (VT2) was assessed by using the ventilatory equivalents for oxygen and carbon dioxide. Results: A two-way ANOVA with repeated measures (substance × time) revealed statistically significant main effects of caffeine (p < 0.01) and time (p = 0.04) on the wattage obtained at VT2, although there was no interaction (p = 0.09). In comparison to the placebo, caffeine increased the workload at VT2 on days 1, 4, 6 and 15 of ingestion (p < 0.05). The size of the ergogenic effect of caffeine over the placebo on the workload at VT2 was progressively reduced with the duration of the treatment. In addition, there were main effects of caffeine (p = 0.03) and time (p = 0.16) on VO2 obtained at VT2, with no interaction (p = 0.49). Specifically, caffeine increased oxygen uptake at VT2 on days 1 and 4 (p < 0.05), with no other caffeine–placebo differences afterwards. For heart rate obtained at VT2, there was a main effect of substance (p < 0.01), while the overall effect of time (p = 0.13) and the interaction (p = 0.22) did not reach statistical significance. Heart rate at VT2 was higher with caffeine than with the placebo on days 1 and 4 (p < 0.05). The size of the effect of caffeine on VO2 and heart at VT2 tended to decline over time. Conclusion: Pre-exercise intake of 3 mg/kg/day of caffeine for twenty days enhanced the wattage obtained at VT2 during cycling ramp tests for ~15 days of ingestion, while there was a progressive attenuation of the size of the ergogenic effect of caffeine on this performance variable. Therefore, habituation to caffeine through daily ingestion may reduce the ergogenic effect of this stimulant on aerobic exercise of submaximal intensity.

The Added Value of a Behavioral Medicine Intervention in Physiotherapy on Adherence and Physical Fitness in Exercise-Based Cardiac Rehabilitation (ECRA): A Randomised, Controlled Trial.

PurposeDespite beneficial effects, adherence to exercise-based cardiac rehabilitation (exCR) is low in patients with coronary artery disease (CAD). The aim of this study was to investigate adherence to and the effects of a behavioral medicine intervention in physiotherapy (BMIP) added to routine exCR care on the primary outcome of physical fitness compared with routine exCR care.Patients and MethodsIn a randomized, controlled trial, 170 patients with CAD (136 men), mean age 62.3 (7.9) years, were included at a Swedish university hospital. Patients were randomized 1:1 to routine exCR care (RC) or to a BMIP added to routine exCR care for four months, with a long-term follow-up at 12 months. The outcome assessment included submaximal aerobic exercise capacity, muscle endurance and self-reported physical activity and physical capacity.ResultsThe four-month follow-up showed improvements in all outcomes for both groups, but changes did not differ significantly between the groups. Patients in the BMIP group were more adherent to exCR recommendations compared with the RC group (31% vs 19%) and a non-significant tendency towards the maintenance of submaximal aerobic exercise capacity over time was seen in the BMIP group, whereas patients in the RC group appeared to deteriorate.ConclusionBoth groups improved significantly at the four-month follow-up, while the 12-month follow-up showed a non-significant tendency towards better long-term effects on submaximal aerobic exercise capacity and exercise adherence for a BMIP compared with RC. In spite of this, a better understanding of the role of a BMIP in enhancing adherence is needed.

The relation between submaximal aerobic exercise improving vascular elasticity through loss of visceral fat and antihypertensive

ABSTRACT Purpose: We sought to observe the effect of submaximal aerobic exercise on abdominal obesity in hypertension patients and to clarify a correlation between blood pressure improvement and visceral fat, along with arterial elasticity. Materials and Methods: According to the treatment plan, the patients were divided into two groups: the combined treatment group and the single drug group. During the training period, the subjects in the combined treatment group performed a 60 min treadmill exercise at 65% of Pmax. PWV was measured using blood pressure pulse-wave detectors before and after treatment. We assessed carotid stiffness and visceral fat area by B‑mode ultrasonography. Results: The 24-h SBP and DBP changed significantly in the two groups in the pre- and post-treatment comparison. Significant statistical differences among SBP and DBP in the two groups of combination therapy and drug therapy after 12 months were demonstrated. Visceral fat area was significantly reduced in the combination therapy group compared to the drug therapy group at the last assessment. Compared with the drug group, arterial compliance in the combination therapy group was higher after treatment. Blood pressure showed significant positive correlation with visceral fat area, PWV, β‑stiffness, Ep, and PWVβ in the combination therapy group. Conclusion: The combination of drug therapy and is more effective than just pursuing single drug treatment of hypertension in patients with abdominal obesity. Submaximal aerobic exercise contributes to anti-hypertension. The main mechanism of anti-hypertension in combination with drug therapy and submaximal aerobic exercise is the improvement of vascular elasticity and decreased central body-fat distribution.

Breath acetone change during aerobic exercise is moderated by cardiorespiratory fitness

Exhaled breath acetone (BrAce) was investigated during and after submaximal aerobic exercise as a volatile biomarker for metabolic responsiveness in high and lower-fit individuals in a prospective cohort pilot-study. Twenty healthy adults (19–39 years) with different levels of cardiorespiratory fitness (VO2peak), determined by spiroergometry, were recruited. BrAce was repeatedly measured by proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF-MS) during 40–55 min submaximal cycling exercise and a post-exercise period of 180 min. Activity of ketone and fat metabolism during and after exercise were assessed by indirect calorimetric calculation of fat oxidation rate and by measurement of venous β-hydroxybutyrate (βHB). Maximum BrAce ratios were significantly higher during exercise in the high-fit individuals compared to the lower-fit group (t-test; p= 0.03). Multivariate regression showed 0.4% (95%-CI = −0.2%–0.9%, p= 0.155) higher BrAce change during exercise for every ml kg−1 min−1 higher VO2peak. Differences of BrAce ratios during exercise were similar to fat oxidation rate changes, but without association to respiratory minute volume. Furthermore, the high-fit group showed higher maximum BrAce increase rates (46% h−1) in the late post-exercise phase compared to the lower-fit group (29% h−1). As a result, high-fit young, healthy individuals have a higher increase in BrAce concentrations related to submaximal exercise than lower-fit subjects, indicating a stronger exercise-related activation of fat metabolism.

The Effect of Physical Activity on Bone Biomarkers in People With Osteoporosis: A Systematic Review

BackgroundBone imbalance between anabolic and catabolic processes at the level of remodeling unit due to the prevalence of resorbing activity, represents a health problem of aging. The consequence is the negative balance of bone turnover that can lead to osteoporosis. Physical activity (PA) can play a central role in the comprehensive management of osteoporosis, since it induces the anabolism of bone tissue. Bone turnover biomarkers, reflecting the cellular activity linked to bone metabolism, can represent an evaluation tool to assess the efficacy of PA in the osteoporotic population. The aim of this systematic review, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, was to investigate the effects of PA interventions on bone biomarkers in people with osteoporosis.MethodsA comprehensive literature search of electronic databases was conducted through PubMed, Cochrane, Cinahl, Embase, Trip, to find randomized controlled trials (RCTs) investigating the topic of PA and bone turnover biomarkers in the osteoporosis population. In accordance with the Cochrane risk-of-bias tool, the quality of each study was assessed.ResultsOut of 992 identified articles, 136 full texts were screened. Only three RTCs matched the eligibility criteria. In one study, sub-maximal aerobic exercise improved Bone-specific alkaline phosphatase (bone formation biomarker) and Amino-terminal Crosslinked Telopeptide of type 1 collagen (bone resorption biomarker) in osteoporotic women. The other two studies showed a positive effect on total alkaline phosphatase (a non-specific bone formation biomarker) in women with osteoporosis.ConclusionThe systematic review revealed possible exercise benefits in terms of improving bone formation and decreasing bone resorption biomarkers in the osteoporotic population. However, these results should be interpreted with caution, especially due to the limited number and poor quality of the studies included. Further research is needed to estimate the influence of PA on bone biomarkers in the osteoporosis management.

Intermittent pneumatic compression changes heart rate recovery and heart rate variability after short term submaximal exercise in collegiate basketball players: a cross-over study

The aim of the study is to assess the effect of intermittent pneumatic compression (IPC) on heart rate recovery and heart rate variability (HRV) after submaximal aerobic exercise in collegiate basketball players. Sixteen male collegiate basketball players aged between 18 and 25 years were included in this cross-over design with two groups (IPC group and placebo-control group). All participants performed an incremental treadmill test at submaximal intensity followed by 15 min of different recovery modes application. Heart rate recovery at the first minute (HRR1) and second minute (HRR2) after submaximal exercise testing were observed. HRV measures were obtained from 5-min R-R intervals during 10 min of ECG recording before the exercise (baseline) and after 15 min recovery period post-exercise. HRR1 (p = 0.008) showed a significant difference, while HRR2 showed a non-significant difference between IPC and placebo-control groups. There was a significant time effect for all time- and frequency-domain HRV parameters (p < 0.001). Group effect was significant for LF (p = 0.002) and LF/HF (p = 0.001). Also, group × time interaction was found to be significant in all frequency-domain HRV variables (p ≤ 0.003). The results of the present study suggest that IPC is a useful recovery tool for faster HRR1 and changing frequency-domain HRV recovery, suggesting positive vagal reactivation after submaximal exercise in collegiate basketball players.

Postexercise Hypotension, Aortic Pressure And Autonomic Modulation In Men Living With Hiv

A single session of aerobic exercise reduces blood pressure vs. pre-exercise, which is referred as postexercise hypotension (PEH). Changes in cardiac autonomic control and local vasodilatation contribute to PEH. HIV-infected patients present higher risk of hypertension, autonomic and endothelial dysfunction, which may influence the PEH. However, this phenomenon has never been studied in this population. PURPOSE: To investigate the effects of acute aerobic exercise upon systemic blood pressure, aortic pressure, and cardiac autonomic modulation in men living with HIV. METHODS: After cardiopulmonary exercise testing, 10 HIV-infected (HIV: 47.5 ± 9.7 yrs; 25.2 ± 3.0 kg.m-2) and 14 healthy men (CTL: 40.1 ± 10.5 yrs; 25.8 ± 3.4 kg.m-2) underwent cycling bouts expending 150 kcal at 50% oxygen uptake reserve (time to achieve 150 kcal - HIV: 24.1 ± 5.5 and CTL: 23.1 ± 3.0 min) and control sessions (20 min), in a randomized counterbalanced order. Systolic blood pressure (SBP), aortic pressure, and heart rate variability were assessed 30 min before and 60 min after each session, by means of oscillometric digital monitor, pulse wave reflection (tonometry), and beat-to-beat heart rate intervals, respectively. Comparisons within-between sessions were made using 2-way ANOVA with repeated measures (P ≤ 0.05). RESULTS: No difference was detected between groups for maximal oxygen uptake (HIV: 27.3 ± 4.2 vs. CTL: 31.4 ± 6.8 mL·kg-1·min-1; P= 0.1) and SBP at rest (HIV: 117.2 ± 11.6 vs. CTL: 112.2 ± 8.9 vs mmHg; P= 0.2). Resting aortic pressure was higher in HIV (107.0 ± 9.3 mmHg) vs. CTL (100.0 ± 4.3 mmHg; P= 0.03), while standard deviation of NN intervals (SDNN) was lower in HIV (28.3 ± 11.2 ms) vs. CTL (43.9 ± 20.8 ms; P= 0.04). In CTL, SBP (-9.3 ± 5.9 mmHg; P= 0.01), aortic pressure (-6.3 ± 4.6 mmHg; P= 0.03), and SDNN (-23.4 ± 44.5 ms; P= 0.05) decreased after submaximal exercise vs. control sessions. No significant change occurred in HIV for SBP (-4.2 ± 18.9 mmHg; P= 0.5), aortic pressure (-5.1 ± 13.0 mmHg; P= 0.2), or SDNN (+5.5 ± 25.6 ms; P= 0.4). CONCLUSION: Healthy, but not HIV-infected men, exhibited acute blood pressure reduction after submaximal aerobic exercise. The higher central arterial stiffness and lower vagal modulation among HIV patients may help to explain the absence of PEH in this group. Supported by FAPERJ Grant.

Acute Adolescent Concussion: Cerebrovascular Reactivity, Symptom Burden, And Exercise Response

Cerebral vasoreactivity (CVR) disruptions have been observed following concussion, which may exacerbate concussion-related symptoms. These CVR disruptions may also influence the cerebral blood flow (CBF) responses during aerobic exercise and thus limit exercise capacity post-concussion. PURPOSE: To examine the relationships between concussion-related symptoms, cerebral vasculature’s ability to respond to changes in CO2 (vasoreactivity), and CBF responses during sub-maximal aerobic exercise in adolescents post-concussion. METHODS: : Adolescents less than two weeks post-concussion completed the Post-Concussive Symptom Checklist (PCSC), cerebral vascular assessments, and a modified YMCA exercise protocol. CVR at rest was estimated from the slope (cm/s/mmHg) of the relationship between the increases in breath-by-breath end-tidal CO2 and responses of CBF velocity during an air rebreathing task (i.e., increasing end-tidal CO2). CBF velocity was measured via transcranial Doppler ultrasonography at the M1 segment of the middle cerebral artery unilaterally during the air rebreathing task and during the aerobic exercise test. Only physical and vestibular-related symptoms were included in analysis: headache, nausea, balance problems, dizziness, fatigue, and % activity level. Two stepwise linear regressions were conducted to test (1) if concussion symptoms are related to CVR and (2) if CVR predicted relative change in CBF velocity during the aerobic exercise test. RESULTS: The majority of the variance in CVR was explained by symptoms of nausea, dizziness, as well as current physical activity levels. Age, sex, resting heart rate, balance, and fatigue also contributed to a lesser degree. Exercise caused a significant increase in MCA blood flow (p<0.001). This exercise induced increase in CBF was largely explained by CVR and estimated VO2peak, with resting heart rate, prior concussion(s), and time since injury also contributing. CONCLUSIONS: Our findings suggests that symptom burden is related to disruptions in CVR in adolescents in the early weeks after a concussion. In turn, the cerebral blood flow response to exercise was related to both CVR and aerobic capacity, suggesting that disruptions in CVR may impact exercise tolerance post-concussion.