Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme最新文献

The low fermentable oligo-, di- and monosaccharides, and polyols (FODMAPs) diet has proven beneficial for the management of irritable bowel syndrome (IBS). The growing demand and limited availability of registered dietitians specialized in IBS, together with the omnipresence of technology in daily life, provide an opportunity for the development of adapted resources. This study aimed to assess the impact of implementing the low FODMAP diet, through an online educational service platform, on the quality of life of patients living with IBS. A prospective single-group intervention pilot study involving patients with IBS from two hospitals was conducted. Participants followed the low-FODMAP diet using a web-based platform for 6 months. The IBS quality of life questionnaire (IBS-QoL), the IBS symptom severity scoring system (IBS-SSS), and the State-Trait Anxiety Inventory Form Y were completed at baseline, after the restriction phase and after reintroduction phase. Fifteen of the 35 recruited participants completed the study (80.0% female, median age of 43.0 (36.0-52.0) years) and at 6 months, a trend towards IBS-QoL improvement was observed, along with a significant improvement in IBS-SSS (from 276 to 200; p < 0.05) and state anxiety level (from 44 to 33; p < 0.05). The results of this pilot study provide valuable insights for the design of a larger study, with promising relevance and utility of teaching the low-FODMAP diet using alternative educational methods.

Multivitamin/mineral (MVM) supplements are widely used in North America, presenting important implications for the practice of primary care, especially in Canada where practitioners frequently serve as patients' initial source of health guidance. The aim of this study is to determine the prevalence of MVM supplement use and the nutrient contribution of MVM supplements to the nutrient intake of Canadians. Dietary data from respondents >1 year in the Canadian Community Health Survey 2015 were used to estimate the prevalence of nutrient adequacy and intakes greater than the upper limit (UL). The National Cancer Institute method was used to estimate usual intakes of vitamin A, C, and magnesium. The prevalence of MVM consumption, as well as any individual vitamin and mineral supplement use, were 24.78% and 19.16%, respectively. Usage was most common among children aged 1-8 years and women over 51 years, particularly among nonobese children and higher-income households. Supplement users show a lower prevalence of nutrient inadequacy from dietary sources alone compared to nonusers of supplements. Also, supplement use is associated with a lower prevalence of nutrient inadequacy compared to nonusers. This study highlights that while MVM supplement use does contribute to overall dietary intake, current MVM supplement use is generally associated with markers of higher socio-economic status and thus those already consuming a healthy diet and less likely to need MVM supplemental nutrients. Aside from population subgroups with specific supplement recommendations (e.g., folic acid in women of childbearing age), dietary guidelines should continue to emphasize meeting nutrient requirements from a wide variety of foods.

Referral to, participation in, and execution of cardiac rehabilitation programs are comparatively lower in females than in males. The current study aimed to explore potential sex disparities in cardiorespiratory capacity and clinical outcomes after cardiac rehabilitation for coronary artery disease. Systematic searches were conducted across the PubMed, Embase, Cochrane Library, and Web of Science databases to identify studies assessing primary outcomes of cardiorespiratory capacity (peak oxygen uptake, peak metabolic equivalents, and its changes), secondary outcomes of cardiovascular endpoints (all-cause mortality, myocardial infarction, rehospitalization) and quality of life following cardiac rehabilitation in both female and male patients with coronary artery disease. A total of 22 predominantly observational studies involving 27 624 patients were analyzed, with 7441 (26.9%) being female and 20 183 (73.1%) being male. After cardiac rehabilitation, females showed lower peak oxygen uptake (mean difference -4.82, 95% confidence intervals -6.30 to -3.34 mL/kg/min, P < 0.00001), peak metabolic equivalents (-1.74, -2.34 to -1.14 units, P < 0.001) and its absolute changes from baseline (-0.40, -0.44 to -0.36 units, P < 0.001), as well as the worse quality of life when compared to males. However, there were no significant sex variations in all-cause mortality, myocardial infarction, and rehospitalization. In conclusion, females exhibited lower cardiorespiratory capacity and quality of life than males following cardiac rehabilitation. Despite these disparities, no sex-based differences existed in cardiovascular outcomes during the follow-up period after cardiac rehabilitation in patients with coronary artery disease. (Registration No. CRD42021269222).

There is growing interest to include exercise into healthcare for the prevention, treatment, and management of chronic disease. However, what defines an "exercise professional" to fulfil these roles and responsibilities is not clear across Canada. While exercise science often integrates exercise professionals within academic studies to assist exercise-based research, exploring how exercise professionals are involved in these contexts may contribute to developing a clearer understanding of how these professionals may be characterized. The purpose of this narrative review was to summarize how exercise professionals are described in research and identify the components that inform their unique roles. A keyword search of "exercise professional" was performed in multiple databases, including Medline, SportDiscus, and Web of Science to identify peer-reviewed studies that included "exercise professionals". Fifteen studies were included, and two independent reviewers performed a reflexive thematic analysis to derive three themes that represent how exercise professionals were described: (1) job title; (2) roles/duties (e.g., fitness testing, motivational interviewing), and (3) education/qualifications/credentials. Common occupations involved in research included exercise physiologists, kinesiologists, and personal trainers. Exercise professionals were responsible for interacting with clinical and non-clinical populations in a variety of contexts. Similarly, qualifications varied, with some studies specifying further training to work with special populations (e.g., patients who have cancer). By identifying these discrepancies, this study highlights the need to develop consistent definitions and roles to promote recognition and integration of exercise professionals in both clinical and community settings.

Despite the general population seeking out exercise professionals and the strong interest of other healthcare providers in referring patients to exercise professionals, what characterizes an "exercise professional" is poorly understood. The purpose of this study was to summarize the required qualifications and certifications described in job advertisements hiring an "Exercise Professional" in Canada. A common career finding website (Indeed) and other relevant organizations were searched for job advertisements. The specific search terms were "Kinesiology", "Kinesiologist", "Exercise Professional", and "Exercise Physiologist". Job advertisements that were hiring an exercise professional and described some exercise related duties were included for content analysis. n = 177/1364 unique job advertisements met inclusion criteria. Job titles were grouped into six main categories: Kinesiologist (n = 88/177), Personal Trainer (n = 49/177), Fitness Coach/Instructor (n = 38/177), Strength and Conditioning Specialist (n = 5/177), Exercise Physiologist (n = 4/177), and other (n = 31/177). Most positions required (n = 101) or preferred (n = 36) a Kinesiology degree, while n = 48/92 (88 Kinesiology and 4 Exercise Physiologist positions) indicated a need/interest in applicants having a membership with a provincial Kinesiology association/affiliation, n = 8/92 a Clinical Exercise Physiologist certification, and n = 6/92 a general "Kinesiology certification". This emphasizes the need for unique requirements of exercise professional positions and guidelines for the (di)similar scope of practice across exercise professional training.

Wildland firefighters can work at high intensity in hot environments for extended periods of time. The resulting heat strain may be modified by the environmental conditions (i.e., ambient temperature and humidity [RH]) even at equal wet-bulb globe temperatures (WBGTs). This investigation assessed if a hot and dry condition would create greater strain than moderate and high humidity at equivalent WBGT (28 °C). Twelve participants (age 24 ± 2 year) walked at 40%-50% maximum aerobic capacity for 90 and 40 min separated by a 20 min rest in dry (40 °C, 20% RH), moderate-humidity (34 °C, 50% RH), and high-humidity (29 °C, 90% RH) conditions wearing fire-resistant jacket, pants, gloves, and helmet with the neck and face exposed. Peak core temperature was higher in moderate-humidity (38.9 ± 0.2 °C, p = 0.01) and high-humidity (38.9 ± 0.6 °C, p < 0.01) than dry condition (38.5 ± 0.3 °C). Average net heat gain was less in dry (33 ± 22 W) compared to moderate-humidity (38 ± 23 W, p < 0.01) and high-humidity (39 ± 28 W, p < 0.01). Peak heart rate (174 ± 14 bpm, p = 0.94), physiological strain index (7.7 ± 1.4 score, p = 0.99), perceived exertion (8 ± 2 rating, p = 0.97), and perceptual strain index (7.3 ± 1.6 score, p = 0.99) were not different in high-humidity compared to the dry condition (167 ± 19 bpm, 6.9 ± 1.3 score, 6 ± 2 rating, 7.3 ± 1.7 score, respectively). Whole-body sweat rate (15 ± 6 mL/min, p = 0.58) and thermal sensation (7 ± 1 rating, p = 0.37) were not different. Hiking in a humid condition while wearing protective garments creates greater exertional heat strain compared to a dry condition of equivalent WBGT. Wildland firefighters should consider extra strategies to mitigate hyperthermia when humidity is high.

Brain-derived neurotrophic factor (BDNF) is a growth factor associated with a range of neurological, cardioprotective, and metabolic health benefits. While passive heat stress has been observed to increase circulating BDNF, the BDNF response to a given stressor may be attenuated with increasing age. To investigate the influence of age on the BDNF response to heat stress, we compared BDNF responses to daylong (9 h) exposure to hot ambient conditions (40 °C, 9% relative humidity) between 19 young (range: 19-31 years; 9 women) and 37 older adults (61-78 years; 12 women). We also explored whether cumulative thermal strain (area under the curve of rectal and mean body temperatures) impacted comparisons. Serum BDNF concentrations were assessed at pre- and end-exposure using enzyme-linked immunosorbent assays. Circulating BDNF concentrations increased from baseline in both groups (P < 0.001), but end-exposure concentrations were 2594 [1555-3633] pg/mL lower in older than young adults (P < 0.001). This age-related difference persisted, albeit to a lesser magnitude, after accounting for the lower pre-exposure BDNF levels in older adults (baseline-adjusted between-group difference: 1648 [667-2630] pg/mL; P < 0.001). Additionally, the BDNF response was not related to indices of thermal strain (P ≥ 0.562), and baseline-adjusted between-group differences were not appreciably altered by adjusting for area under the curve of rectal (1769 [714-2825] pg/mL; P = 0.002) or mean body temperatures (1745 [727-2763] pg/mL; P = 0.001). Our study is the first to demonstrate an age-related reduction in the BDNF response to prolonged passive heat exposure, which informs our wider understanding of how environmental stressors influence BDNF responses in older adults.

Athletes may engage in weight cycling-successive episodes of weight loss and weight (re)gain-for performance reasons, but risk metabolic adaptations and regaining more fat that was lost (fat overshoot). This study aimed to assess the influence of a complete weight cycling episode on body composition, thermoregulation, and metabolism in athletes, considering sex and the type of sport practiced. Forty-eight athletes (28 males, 20 females) engaged in combat (n = 23), strength (n = 12), or endurance (n = 13) sports were examined under three experimental conditions (weight maintenance, weight loss, weight (re)gain) during a weight cycling episode using their habitual strategies. Body composition (dual-energy X-ray absorptiometry), core body temperature (telemetric temperature sensor), energy expenditure and substrate oxidation at rest and during moderate exercise (indirect calorimetry), and energy intake (48 h food record) were assessed. Overall, athletes lost 4.4 ± 2.3% body weight, 12.2 ± 10.6% fat mass, and 2.6 ± 2.3% fat-free mass (p < 0.001). All variables returned to baseline values during the regain period, and a higher fat mass regain was observed in endurance than combat athletes (p < 0.01). During weight loss, a transient increase in lipid and decrease in carbohydrate oxidation occurred at rest and during exercise (p < 0.001). Energy expenditure and core body temperature remained unchanged across the three experimental conditions, and no specific sex effect was observed. Overall, no apparent body weight nor fat overshoot was observed in athletes after a complete weight cycling episode. Nonetheless, the greater fat mass gain in endurance, compared with combat athletes, highlights a need for further specific long-term studies in this population. Clinical Trial registration: NCT04107545.

The present study aimed to compare peak oxygen uptake (V̇O₂peak), peak heart rate (HRpeak), and peak O₂pulse during an incremental and a verification test performed on the same day in hand-cyclists with spinal cord injury (SCI). Eight competitive SCI hand-cyclists (age: 23 ± 2.7 years; V̇O₂peak: 36.3 ± 14.0 mL.kg^-1.min^-1) performed a maximal incremental handcycling test and a verification test to exhaustion at 100% of the peak speed on an oversized treadmill. The V̇O₂peak, HRpeak, and peak O₂pulse (i.e., VO₂/HR) were compared between incremental and verification tests. Absolute and relative V̇O₂peak obtained in the verification test (2.51 ± 0.96 L.min^-1; 36.3 ± 14.0 mL.kg.min^-1) were significantly higher than values obtained in the incremental test (2.24 ± 0.79 L.min^-1; 33.5 ± 12.9 mL.kg.min^-1; P < 0.05). The mean differences (95% CL) of absolute and relative V̇O₂peak between tests were 8.2% (3.3%-13.2%) and 10.9% (4.3%-18.1%), respectively. There was no difference in HR peak (incremental: 169 ± 24 bpm; verification 167 ± 25 bpm; P = 0.130). Peak O₂pulse from the verification test (14.6 ± 4.7 mL.beat^-1) was higher than incremental test (13.0 ± 3.8 mL.beat^-1; P = 0.007). In conclusion, the verification test elicited greater V̇O₂peak and O₂pulse than a two-phase incremental test despite the similar HRpeak. This indicates that for this progressive protocol lasting ≥25 min, the verification phase adds value to determining V̇O₂peak in SCI athletes.

Motor unit firing rate (MUFR) and pennation angle were measured concurrently in males and females from submaximal to maximal intensities. Thirty participants, (16 female, 14 male) performed isometric dorsiflexion contractions at 20%, 40%, 60%, 80%, and 100% of maximal voluntary contraction (MVC). During each contraction, measures of MUFR were obtained via surface electromyography decomposition, and muscle fiber pennation angle and fascicle length were obtained via ultrasound. There was no significant interaction effect of sex and contraction intensity present for mean MUFR (p = 0.24), pennation angle (p = 0.98), or fascicle length (p = 0.81). Males had greater mean MUFR (p < 0.001), pennation angle (p = 0.02), and fascicle length (p = 0.03) compared to females. In general, mean MUFR (p < 0.001) and pennation angle (p < 0.02) increased with increasing contraction intensity; however, fascicle length (p = 0.30) was similar across contraction intensities. There were no significant relationships between mean MUFR and pennation angle for males (r = 0.18, p = 0.13) or females (r = 0.20, p = 0.09), nor between mean MUFR and fascicle length for males (r = 0.20, p = 0.10) or females (r = 0.21, p = 0.07). Although sex-related differences in MUFR, pennation angle, and fascicle length were present, there were no relationships between MUFR and the muscle properties. These results suggest that sex-related differences in mean MUFR may not be associated with the sex-related differences in the muscle architectural properties currently investigated.