Increasing aerobic exercise intensity fails to consistently improve the glycemic response in people living with prediabetes or type 2 diabetes mellitus: the INTENSITY trial.

Some individuals with prediabetes or type 2 diabetes mellitus (T2DM) who engage in exercise will not experience the anticipated improvements in glycemic control, referred to as non-responders. Increasing exercise intensity may improve the proportion of individuals who become responders. The objectives were to (i) identify responders and non-responders based on changes in glycated hemoglobin (HbA1c) in individuals with prediabetes or T2DM following 16 weeks of aerobic exercise; (ii) investigate if increasing exercise intensity enhances the responders' status for individuals not previously responding favourably to the intervention. Participants (n = 40; age = 58.0 years (52.0-66.0); HbA1c = 7.0% (6.0-7.2)) engaged in a two-phase, randomized study design. During phase one, participants performed 16 weeks of treadmill-based, supervised, aerobic exercise at 4.5 metabolic equivalents (METs) for 150 min per week. Thereafter, participants were categorized as responders, non-responders, or unclear based on the 90% confidence interval above, below, or crossing a 0.3% reduction in HbA1c. For phase two, participants were randomized to a maintained intensity (4.5 METs) or increased intensity (6.0 METs) group for 12 weeks. Following phase one, two (4.1%) participants were categorized as responders, four (8.2%) as non-responders, and 43 (87.7%) as unclear. Following phase two, two from the increased intensity group and one from the maintained intensity group experienced an improvement in response categorization. There were no significant between or within group (maintained vs. increased) differences in HbA1c. For most people with prediabetes or T2DM, increasing exercise intensity by 1.5 METs does not improve response categorization.

Resistance Training on an Outdoor Exercise Structure Improves Lower-Body Relative Strength in Older Adults.

Improving relative strength is important for maintaining functionality with age, and outdoor exercise structures could be useful to facilitate this. A total of 29 adults aged 65+ participated in a non-randomized crossover study with a 6-week control followed by a 6-week resistance training intervention on an outdoor exercise structure (3x/week). Relative strength (predicted maximal leg press/lower body lean mass [Dual-energy X-ray Absorptiometry]) and physical function variables were measured at baseline, post-control, and post-intervention. Represented as median (25th-75th), lower body relative strength improved from 7.91 (7.01-9.35) post-control to 8.50 (7.99-9.72) post-intervention (p = .002) in study completers (n = 17). Maximum leg press (p = .002), 30-second chair stand (p < .001), one-leg stance (p = .011), and maximum chest press (p = .009) also improved significantly during the intervention. There were no significant changes in aerobic activity, grip strength, lean mass, or muscle power. This study demonstrates that there could be potential relative strength benefits associated with the use of outdoor exercise structures in older adults.

Comparing Online and In-Person Delivery of a Fall Prevention Exercise Program for Older Adults.

Exercise is the single most effective strategy to reduce the risk of falls. Online classes have grown in popularity, but the benefits of online classes remain unknown. Zoomers on the Go is a peer-led 12-week exercise program offered twice weekly to adults 50+ years old. The main outcome was lower body strength measured by the 30-s chair stand test. Other outcomes included dropout, attendance, balance, cardiorespiratory fitness, and perceived health. A total of 74 participants (age 66.3 ± 7.1 years) in the online group and 84 participants in the in-person group (age 67.3 ± 7.2 years) completed the program, with attendance for the online group. Both groups significantly improved their 30-s chair stand, cardiorespiratory fitness, and balance (p < .001) with no difference in functional benefits between groups. The in-person group improved their perceived health and significantly reduced levels of stress and depression, while no such changes were observed in the online group.

Online exercise program for men living with obesity: Experiences, barriers, and enablers.

The prevalence of obesity is increasing among men, and this population remains under-represented in lifestyle and weight management interventions. The current study aims to explore the experiences of men living with obesity (body fat ≥25 %) toward a 12-week supervised online exercise platform. Ten men were interviewed for this qualitative study. Semi-structured, open-ended phone interviews were conducted, and the transcripts were thematically coded using the qualitative data analysis Nvivo QSR software package. The research findings are illustrated using quotes from participants. The results were organized into two main themes: those that removed barriers to exercise and those that improved the enablers of exercise. Eliminating barriers included not purchasing specialized equipment or travelling to a gym facility. The enablers to their success with the program included the structured format of the circuit program and having supervised sessions. By removing barriers and enhancing enablers, the 12-week online exercise circuit program increased compliance to and success of the exercise program for men living with obesity. Future research should explore the long-term effects of an online program for men living with obesity and its appeal beyond COVID-19.

Online Circuit Training Increases Adherence to Physical Activity: A Randomized Controlled Trial of Men with Obesity.

PURPOSE: This study aimed to examine adherence to the weekly physical activity guidelines (≥150 min of aerobic activities at moderate-to-vigorous intensity and two or more sessions of strength training (yes or no)) and health outcomes during the COVID-19 pandemic for men living with obesity, 46 wk after being offered an online muscle-strengthening circuit program for 12 wk. METHODS: Sixty men (age ≥19 yr) living with obesity (body fat percentage ≥25%) were randomly assigned to the intervention group ( n = 30) or the control condition ( n = 30) for 12 wk. The intervention group was offered an online circuit training, three sessions per week, whereas the control group received a website helping them to reach the physical activity guidelines. Adherence to the weekly physical activity guidelines was evaluated 46 wk after enrolling in the program using a heart rate tracker (Fitbit Charge 3) and an exercise log. Health outcomes (e.g., anthropometrics, body composition) were measured at baseline and after 12, 24, and 46 wk. RESULTS: The intervention group had higher adherence to physical activity guidelines at 46 wk (36.8%) than the control group (5.3%; P = 0.02). However, no difference in health outcomes was observed between participants in the intervention group compared with the control group after 12, 24, and 46 wk. CONCLUSIONS: Increasing adherence to exercise in men living with obesity is challenging. The proposed program increased adherence to the physical activity guidelines after about a year for men living with obesity; however, more studies are needed to understand how to improve health outcomes when following an online delivery exercise program in this population.

The Effect of a Standing Intervention on Falls in Long Term Care: a Secondary Analysis of a Randomized Controlled Trial.

Background: Older adults in long term care (LTC) spend over 90% of their day engaging in sedentary behaviour. Sedentary behaviour may exacerbate functional decline and frailty, increasing the risk for falls. The purpose of this study is to explore the impact of a 22-week standing intervention on falls among LTC residents at 12-month follow-up. Methods: This was a planned secondary analysis of the Stand if You Can randomized controlled trial. The original trial randomized 95 participants (n = 47 control; n = 48 intervention) to either a sitting control or a supervised standing intervention group (100 minutes/week) for 22 weeks. Falls data were available to be collected over 12 months post-intervention for 89 participants. The primary outcome was a hazard of fall (Yes/No) during the 12-month follow-up period. Results: A total of 89 participants (average age 86 years ± 8.05; 71.9% female) were followed for 12-months post-intervention. Participants in the intervention group (n=44) had a significantly greater hazard ratio of falls (2.01; 95% CI = 1.11 to 3.63) than the control group (n=45) when accounting for the history of falls, frailty status, cognition level, and sex. Conclusion: Participants who received a standing intervention over 22 weeks were twice as likely to fall 12 months after the intervention compared with the control group. However, the prevalence of falls did not surpass what would be typically observed in LTC facilities. It is imperative that future studies describe in detail the context in which falls happen and collect more characteristics of participants in the follow-up period to truly understand the association between standing more and the risk of falls.

Long-term care residents' acceptance of a standing intervention: A qualitative intrinsic case study.

Older adults in long-term care are sedentary. Standing is recommended to reduce sedentary time, but there is limited research on long-term care residents' acceptability of standing interventions. The acceptability of the Stand If You Can (SIYC) randomized clinical trial among long-term care residents was explored using a single intrinsic qualitative case study design. The five month intervention consisted of supervised 100 min standing sessions per week. Participants completed post-intervention interviews, which were analyzed using the Thematic Framework Analysis through the lens of an acceptability framework. The 10 participants (7 female), age 73 to 102 years, stood a median of 53% of the intervention offered time (range 20%-94%). The participants reported acceptability in many aspects of the Theoretical Framework of Acceptability. Standing is a simple intervention to decrease sedentary time and seems to be accepted among long-term care residents when burden is not perceived as too high.

Fear of Falls Following an Online Exercise Program for Aging Adults.

Individuals who participate in regular exercise tend to report a lower fear of falling; however, it is unknown if this fear can be reduced following an online fall prevention exercise program. The main purpose of this study was to test if offering a peer-led fall prevention exercise program online reduced the fear of falling and if this potential improvement was greater than when the program was offered in person. The secondary objectives were to describe participants' characteristics when participating online, the rate of falls and the context in which falls occur. A total of 85 adults aged 69.0 ± 7.8 years participated in the program offered online (n = 44) and in-person (n = 41). No significant differences in fear of falling before and after participation in the program were reported for either group: online (20.7 ± 5.1-21.8 ± 5.5) and in-person (20.6 ± 5.1-21.2 ± 5.3). Online participants reported a greater proportion of falls (n = 9; 20.5% vs. n = 4; 9.8%; p = .14), mostly occurring outdoors (n = 7) (77.8). A properly designed study is needed to test if the rate of falls is greater when an exercise program is offered online.

Examining the role of sex on the benefits of muscle-strengthening activities for people living with obesity: A cross-sectional study.

Aims: To investigate the correlations between meeting the muscle-strengthening activities guideline, body fat %, and mortality for individuals living with obesity and to explore if these correlations are moderated by sex. Methods: Data from 3915 adults (51.9% women; 48.1% men ) living with obesity (body fat % ≥25 for men and ≥35 for women) from two cycles of the National Health and Nutrition Examination Survey (NHANES 2003-04/2005-06) were analyzed. Muscle-strengthening activities were self-reported via a questionnaire, body fat % was measured via Dual Energy X-ray, and mortality was obtained via administrative data for an average of 10 years. Results: 18.7% of men and 15.2% of women living with obesity met the muscle-strengthening activities guideline (p = 0.021) . Sex was correlated with body fat %; (ß (SE)= 11.34 (0.18); p ≤ 0.001) and risk of mortality (hazard ratio (95% confidence interval) = 0.36 (0.24-0.54); p ≤ 0.001), once adjusted for confounders (weekly aerobic activities, ethnicity, education, household income, smoking, and the sum of chronic conditions). The interaction between sex and meeting the muscle-strengthening activities guideline was not significantly correlated with the studied outcomes. Conclusion: Performing muscle-strengthening activities a minimum of two times per week does not impact body fat % or risk of mortality (over 10 years) differently in men or women living with obesity.

Impact of a Preoperative Exercise Program on General Fitness in Patients Awaiting Bariatric Surgery: A Pilot Randomized Trial.

Background Evidence supports the association between exercise and outcomes following bariatric surgery. However, there is a lack of knowledge regarding the short-term benefits of preoperative exercise. Objectives The objective of this pilot study was to evaluate the feasibility and functional benefits of a 12-week preoperative exercise program in patients awaiting bariatric surgery. The primary aim was the six-minute walk test (6MWT). The secondary aim of this study included anthropometric measures, strength, and quality of life. Methods A total of 54 patients were enrolled in this pilot randomized controlled study. Of them, 29 patients received standard multidisciplinary preoperative care, while 25 patients participated in a 12-week supervised exercise program in addition to standard preoperative care consisting of strength and aerobic exercises three times per week in a fitness facility. The primary outcome was improvement in 6MWT. Secondary outcomes included other functional outcomes, quality of life, and anthropometric measures. Results Average attendance for the intervention group was 27.2 (75.6%) of 36 sessions. There was a mean improvement of 27 ± 10 meters in the intervention group compared with a reduction of 5 ± 10 meters in the control group (p = 0.003). Patients in the intervention group had significant improvement in all self-reported quality-of-life domains, particularly in the variables related to symptoms, hygiene, and emotions. Conclusions A 12-week preoperative exercise intervention was feasible and showed association with a statistically significant improvement in 6MWT and quality-of-life measures in patients awaiting bariatric surgery. The results of this study will inform sample size calculations and recruitment planning for a future study that will assess the longer-term benefits of a pre-surgical fitness intervention.

Association between physical activity & sedentary time on frailty status in males and females living with diabetes mellitus: A cross-sectional analysis.

BACKGROUND: Physical activity (PA) is a cornerstone for the prevention and the treatment of diabetes mellitus (DM) and frailty. However, no consensus exists on which intensities and types of PA are associated with frailty status among individuals living with DM. To investigate the association between different intensities and types of PA on frailty status in males and females living with DM. METHODS: A cross-sectional analysis of the 2003-2006 cycles from the National Health and Nutrition Examination Survey (NHANES) was performed in 711 participants living with DM. Frailty status was measured using the 43-item deficit model and DM was self-reported. Weekly PA levels were measured by accelerometer, while resistance training (RT) was measured via questionnaire. Linear and logistic regressions were performed to investigate the associations between different intensities and types of PA and frailty status. RESULTS: Total time spent performing light PA was associated with a better frailty status in males (ß - 0.041 ± 0.012; p < 0.001) and females (ß - 0.070 ± 0.010; p < 0.0001), while total moderate-to-vigorous PA (MVPA) was associated with a better frailty status in females only (ß-0.235 ± 0.061; p < 0.05). However, once fully adjusted, the different intensities and types of PA were associated more with frailty status for female. When investigating whether different intensities and types of PA were associated with being considered frail, total time spent at MVPA and light PA were associated with higher odds along with total sedentary time for female (all p < 0.01). CONCLUSION: Each minute engaged in PA was associated with a better frailty status in males and females living with DM, although RT does not appear associated with a better frailty status in adults with DM. Replacing sedentary time with PA is important, especially for females living with DM to have a better frailty status. These results are important as they provide insights into the prevention and the management of frailty in individuals living with DM.

Potential value of home square-stepping exercises for inactive older adults: an exploratory case study.

BACKGROUND: Most older adults do not engage in regular physical activity. However, more research on options to partake in regular exercise in this population by reducing barriers and enhancing enablers while still reaching benefits is needed. METHODS: Using embedded mixed methods, 10 inactive older adults over the age of 65 completed a 3-week square-stepping exercise intervention to help overcome the initial barriers and activate initial enablers to perform regular exercise. Physical activity level was tracked at home with a pedometer using median steps/day over seven days for pre-post measure. Aerobic intensity while doing square-stepping exercises was quantified via a heart rate monitor in a supervised session. Each participant had an interview asking about barriers and enablers to regular exercise and if the intervention could modify any. Based on initial physical activity a framework matrix was used to pull potential barriers to compare, contrast, and search for patterns between participants with lower and higher initial physical activity levels. RESULTS: The 3-week square-stepping exercise intervention helped participants overcome barriers such as being uncomfortable in a fitness facility and body image and activate enablers such as the use of home equipment and convenience. The median total steps/day increased by 12% (p = 0.02), and a moderate-intensity level was reached by 80% of the sample participants when performing the square stepping exercise during a supervised session. Common barriers such as having a suitable program, hard to keep the intensity were reported by participants regardless of the initial physical activity level. CONCLUSION: Regardless of initial physical activity level, inactive older adults can increase physical activity level at the recommended intensity and overcome common barriers to exercise when performing square-stepping exercises, especially for those intimidated by a fitness facility setting and those concerned with their body image. A longer intervention including more participants using the square-stepping exercises is required to understand if square-stepping exercises can increase the proportion of older adults exercising regularly.

Directions for Exercise Treatment Response Heterogeneity and Individual Response Research.

Treatment response heterogeneity and individual responses following exercise training are topics of interest for personalized medicine. Proposed methods to determine the contribution of exercise to the magnitude of treatment response heterogeneity and categorizing participants have expanded and evolved. Setting clear research objectives and having a comprehensive understanding of the strengths and weaknesses of the available methods are vital to ensure the correct study design and analytical approach are used. Doing so will ensure contributions to the field are conducted as rigorously as possible. Nonetheless, concerns have emerged regarding the ability to truly isolate the impact of exercise training, and the nature of individual responses in relation to mean group changes. The purpose of this review is threefold. First, the strengths and limitations associated with current methods for quantifying the contribution of exercise to observed treatment response heterogeneity will be discussed. Second, current methods used to categorize participants based on their response to exercise will be outlined, as well as proposed mechanisms for factors that contribute to response variation. Finally, this review will provide an overview of some current issues at the forefront of individual response research.

Variability in physical function for patients living with breast cancer during a 12-week exercise program.

PURPOSE: To describe the variability during weekly performance on physical function tests during a 12-week individualized exercise program for patients with breast cancer and to test if the expected improvements in physical function surpass the minimally clinically important difference (MCID), after accounting for week-to-week variance. METHODS: Twenty-five participants, 19 years and older living with breast cancer within 2 years of their initial diagnosis, were recruited. Some participants were undergoing active treatment, while others completed their treatment. The intervention was an individualized exercise session twice a week, for 1 h each session, for a total of 12 weeks. Main outcomes tested included the 6-min walk test and chair stand test. RESULTS: A significant average improvement was observed in the 6MWT (p < .01) and the chair stand test (p < .001) following the intervention. Individual confidence intervals were wide across all testing measures with only 28% and 8% of participants meeting or surpassing the MCID for the 6MWT and chair stand test, respectively. CONCLUSION: Despite a significant improvement in physical function during the program, the majority of patients did not reach the MCID, which could be due to large variability resulting from treatment-related side effects or measurement error.

Exploring the Association of a Total Physical Activity Energy Expenditure and Diabetes Mellitus in Adults: A Cross-Sectional Analysis of the Canadian Health Measures Survey.

Background: Physical activity (PA) guidelines for adults recommend participation in aerobic activities of moderate-to-vigorous intensity and a minimum of two sessions of resistance training (RT) weekly. These guidelines account for a small amount of the total PA energy expenditure and include no recommendation for low intensity activities (sleeping, sedentary behavior, and light intensity PA). Consequently, there is a need to investigate the benefits of total PA energy expenditure and diabetes mellitus (DM); to investigate the association between total PA energy expenditure and DM in adults aged 45 years or above. Methods: Data from the Canadian Health Measures Survey (CHMS; n = 5591) were used for the cross-sectional analysis. DM was measured using hemoglobin glycated (A1c) and questionnaires in adults aged 45 and above. PA and sedentary behavior were estimated using accelerometry. Sleep and RT were self-reported. Total PA energy expenditure was computed using the sum of metabolic equivalent of task-min/week. Results: The mean age of the sample was 58.0 ± 0.2 years old. No associations were observed between total PA energy expenditure and self-reported T2DM in all models (P > 0.05). For objectively measured DM, this association was significant when adjusted for age, sex, ethnicity, and smoking [OR: 0.45; 95% CI (0.25-0.80)]; however, the association was no longer significant once adjusted for waist circumference and further adjusted for meeting the International PA Guidelines [OR: 0.64; 95% CI (0.33-1.27)] (P > 0.05). Conclusion: Total PA energy expenditure performed weekly is not associated with DM when considering other known risk factors, including waist circumference and meeting the PA guidelines.

Difference in total workload during sprint interval training for adults living with or without obesity.

PURPOSE: The primary objective of the study was to compare the implications of body composition on work volume, power outputs (peak, mean, and minimum), and relative drop load throughout 4 weeks of sprint interval training (SIT) in individuals living with and without obesity. METHODS: Thirty-four participants living with (n = 16) and without (n = 18) obesity took part in 12 sessions of SIT over 4 weeks. SIT consisted of repeated 30-s Wingate with a drop load of 7.5% of the participant's body mass separated by 4 min of active recovery. Fat-free mass was estimated using a BOD POD. Work volume, drop load, and power output (peak, mean, and minimum) relative to body mass and fat-free mass were calculated using a Monark 874E Weight cycle ergometer. RESULTS: Individuals living with obesity had a significantly larger drop load relative to fat-free mass (p < 0.001) and absolute drop load (p < 0.001) as well as a lower cycling cadence (p < 0.001) compared to individuals without obesity. No significant difference was observed in work volume (p = 0.167) as well as mean (p = 0.903), peak (p = 0.294), and minimum (p = 0.103) power relative to fat-free mass between groups. CONCLUSION: The findings suggest that individuals living with obesity work at a higher relative drop load when utilizing a percentage of body mass; however, a reduced cycling cadence results in similar total work volume throughout SIT.

Effects of sprint interval training on substrate oxidation in adults living with and without obesity: The i-FLEX study.

Metabolic flexibility is the ability to adapt substrate oxidation according to metabolic demand. Exercise increases fat oxidation responses in individuals living with obesity; however, limited research exists on the relationship between substrate oxidation and insulin sensitivity after sprint interval training (SIT). The primary objective was to investigate changes in substrate oxidation at rest and during submaximal exercise, and in insulin sensitivity after 4 weeks of SIT in individuals living with or without obesity. The secondary objective was to investigate correlations between changes in substrate oxidation and insulin sensitivity following SIT. Adults living with obesity (n = 16, body mass index (BMI) = 34.1 kg/m2  ± 3.8) and without obesity (n = 18, BMI = 22.9 kg/m2  ± 1.6) took part in a 4-week SIT intervention. Participants completed three sessions of SIT per week, consisting of repeated sets of a 30-s Wingate separated by 4 m of active recovery. Substrate oxidation at rest and during submaximal exercise was measured using VCO2 /VO2 . Insulin sensitivity was calculated using the Matsuda index. No difference in substrate oxidation at rest was observed for either group (p > 0.05), while a significant increase in fat oxidation was observed in individuals living with obesity [F(1,31) = 14.55, p = 0.001] during the submaximal exercise test. A significant decrease in insulin sensitivity was observed among individuals without obesity [F(1,31) = 5.010, p = 0.033]. No correlations were observed between changes in substrate oxidation and insulin sensitivity (p > 0.05). Following SIT, individuals living with obesity increased submaximal fat oxidation compared to individuals without obesity. No correlations were observed between substrate oxidation and insulin sensitivity. Thus, SIT impacts fat oxidation during exercise in individuals living with obesity while having no such influence on insulin sensitivity.

Impact of acute circuit training on irisin in younger and older overweight adults.

Studies show aerobic exercise increases irisin and leads to health benefits. The impact of circuit training (CT) on irisin in overweight younger and older adults is unknown. The objectives were to determine whether, during an acute bout of CT, changes in irisin differed between overweight younger and older adults, and if irisin is associated with body composition, fitness level, or muscle strength. Inactive, overweight adults aged between 19-35 (25.9 ± 5.0; n = 15) and 60-75 years (67.7 ± 4.1; n = 14) participated in this study. The primary exposure variable was an acute bout of CT (12-15 repetitions; 65-70% of 1-repetition maximum; 3 loops). The primary outcome measure was the concentration of irisin determined by ELISA before, during, and after exercise. Repeated-measures analyses showed no effect of time on irisin levels during acute CT, and no interaction effect between age and time (p > 0.05). No associations were observed between changes in irisin and body composition, fitness, or strength (p > 0.05). In conclusion, acute CT does not increase irisin in overweight individuals, and irisin is not associated with the measured outcomes. Further studies are needed to elucidate the release of irisin by different types of exercise across the lifespan. This trial was registered at clinicaltrials.gov (NCT03715088). Novelty: Younger and older adults show a similar irisin response to an acute bout of circuit training. Irisin response is not associated with measures of body composition, cardiorespiratory fitness, or muscle strength.

Can non-responders be 'rescued' by increasing exercise intensity? A quasi-experimental trial of individual responses among humans living with pre-diabetes or type 2 diabetes mellitus in Canada.

INTRODUCTION: Exercise is recommended to improve glycaemic control. Yet, individual changes in glycaemic control following exercise can vary greatly, meaning while some significantly improve others, coined 'non-responders', do not. Increasing the intensity of exercise may 'rescue' non-responders and help generate a response to training. This trial will identify non-responders to changes in glycated haemoglobin (HbA1c) across inactive individuals living with pre-diabetes or type 2 diabetes mellitus following an aerobic exercise programme and evaluate if increasing training intensity will elicit beneficial changes to 'rescue' previously categorised non-responders. METHODS AND ANALYSIS: This study will recruit 60 participants for a two-phase aerobic exercise training programme. Participants will be allocated to a control group or assigned to an intervention group. Control participants will maintain their current lifestyle habits. During phase 1, intervention participants will complete 16 weeks of aerobic exercise at an intensity of 4.5 metabolic equivalents (METs) for 150 min per week. Participants will then be categorised as responders or non-responders based on the change in HbA1c. For phase 2, participants will be blocked based on responder status and randomly allocated to a maintained intensity, or increased intensity group for 12 weeks. The maintained group will continue to train at 4.5 METs, while the increased intensity group will train at 6.0 METs for 150 min per week. ETHICS AND DISSEMINATION: Results will be presented at scientific meetings and submitted to peer-reviewed journals. Publications and presentations related to the study will be authorised and reviewed by all investigators. Findings from this study will be used to provide support for future randomised control trials. All experimental procedures have been approved by the Research Ethics Board at the University of New Brunswick (REB: 2018-168). TRIAL REGISTRATION NUMBER: NCT03787836.

Acute effects of extruded pea fractions on glycemic response, insulin, appetite, and food intake in healthy young adults, results of a double-blind, randomized crossover trial.

Benefits of pulse consumption on glycemic control are well established; however, research examining the effects of pulse fractions incorporated into extruded products is limited. In a randomized, repeated-measures crossover study, adults (n = 26) consumed cereals made with oat flour (control), oat flour and pea starch (starch), oat flour and pea protein (protein), oat flour, pea starch and pea protein (starch+protein), oat flour, pea fibre and pea protein (fibre+protein), and pea fibre, pea starch and pea protein (fibre+starch+protein). Blood glucose (BG) and insulin concentrations, and appetite incremental area under the curve (iAUC) were calculated before (0-120 min) and after (120-200 min) the ad libitum meal for measurement of food intake. Pre-meal, overall mean BG and iAUC were lower following the protein, starch+protein, protein+fibre, and the fibre+starch+protein cereals compared with the starch and control. For pre-meal overall mean insulin concentrations, fibre+protein led to a lower response compared with control, starch+protein, and protein cereals. Fibre+starch+protein also led to lower insulin compared with protein cereal. Pre-meal insulin iAUC was lower following fibre+protein compared with control and protein cereals. The inclusion of yellow pea protein and fibre in oat-based breakfast cereal reduces postprandial glycemia; however this effect is dependent on fraction type. ClinicalTrials.gov: NCT02366572. Novelty: Inclusion of pulse protein and fibre in oat flour-based breakfast cereal reduces postprandial glucose response. The glycemic benefits of whole pulses are at least somewhat retained in some pulse fractions.