Climate change, biodiversity loss, and Indigenous Peoples' health and wellbeing: A systematic umbrella review.

Indigenous Peoples worldwide are experiencing a cascade of impacts on their health and wellbeing as a result of climate change and biodiversity loss. Existing literature at the interface of climate change, biodiversity loss, and Indigenous health tells us that Indigenous Peoples are among those most disproportionately and acutely affected by these impacts. Yet, a gap exists with respect to comprehensively and critically synthesizing the impacts reported across this literature and identifying Indigenous-led responses. Guided by an Indigenous advisory group, we employed a systematic umbrella review methodology, following PRISMA guidelines, to characterize the global secondary literature (PROSPERO registration #: CRD42023417060). In so doing, we identified the proximal, intermediate, distal, and gendered impacts of climate change and biodiversity loss on Indigenous health and wellbeing as well as Indigenous-led responses. Five databases were searched for published reviews, along with a grey literature search that focused on underrepresented geographic regions in the academic literature. Two independent reviewers conducted two-stage screening, data extraction, and quality assessment of retrieved records. Basic descriptive statistics were calculated. Qualitative data were analyzed thematically, using a constant comparative approach. A total of 38 review articles met the eligibility criteria and 37 grey literature records were retrieved and included in the review. Reviews were published between 2010-2023 and geographically clustered in the Circumpolar North. Intersecting proximal, intermediate, and distal impacts were characterized as place-based and specific, and linked to colonialism as an antecedent to and driver of these impacts. Gendered impacts were underexplored within reviews. Reviewed literature underscored the value of engaging diverse knowledge systems; platforming localized, community-led adaptation to climate change and biodiversity loss, while addressing sociopolitical constraints to these efforts; and applying a broader conceptualization of health that aligns with Indigenous frameworks. Going forward, we must foreground equity- and rights-based considerations within integrated responses to climate and biodiversity crises.

Climate change, biodiversity loss, and Indigenous Peoples' health and wellbeing: a systematic umbrella review protocol.

BACKGROUND: Research that examines the intersections of Indigenous Peoples' health and wellbeing with climate change and biodiversity loss is abundant in the global scholarship. A synthesis of this evidence base is crucial in order to map current pathways of impact, as well as to identify responses across the global literature that advance Indigenous health and wellbeing, all while centering Indigenous voices and perspectives. This protocol details our proposed methodology to systematically conduct an umbrella review (or review of reviews) of the synthesized literature on climate change, biodiversity loss, and the health and wellbeing of Indigenous Peoples globally. METHODS: A multidisciplinary team of Indigenous and non-Indigenous scholars will conduct the review, guided by an engagement process with an Indigenous Experts group. A search hedge will be used to search PubMed®, Scopus®, Web of Science™, CINAHL (via EBSCOHost®), and Campbell Collaboration databases and adapted for use in grey literature sources. Two independent reviewers will conduct level one (title/abstract) and level two (full-text) eligibility screening using inclusion/exclusion criteria. Data will be extracted from included records and analyzed using quantitative (e.g., basic descriptive statistics) and qualitative methods (e.g., thematic analysis, using a constant comparative method). DISCUSSION: This protocol outlines our approach to systematically and transparently review synthesized literature that examines the intersections of climate change, biodiversity loss, and Indigenous Peoples' health and wellbeing globally. SYSTEMATIC REVIEW REGISTRATION: This protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on April 24, 2023 (registration number: CRD42023417060).

Mixed methods pilot study of a low-carbohydrate diabetes prevention programme among adults with pre-diabetes in the USA.

OBJECTIVES: (1) To estimate weight change from a low-carbohydrate diabetes prevention programme (LC-DPP) and (2) to evaluate the feasibility and acceptability of an LC-DPP. RESEARCH DESIGN: Single-arm, mixed methods (ie, integration of quantitative and qualitative data) pilot study. SETTING: Primary care clinic within a large academic medical centre in the USA. PARTICIPANTS: Adults with pre-diabetes and Body Mass Index of ≥25 kg/m2. INTERVENTION: We adapted the Centers for Disease Control and Prevention's National Diabetes Prevention Program (NDPP)-an evidence-based, low-fat dietary intervention-to teach participants to follow a very low-carbohydrate diet (VLCD). Participants attended 23 group-based classes over 1 year. OUTCOME MEASURES: Primary outcome measures were (1) weight change and (2) percentage of participants who achieved ≥5% wt loss. Secondary outcome measures included intervention feasibility and acceptability (eg, attendance and qualitative interview feedback). RESULTS: Our enrolment target was 22. One person dropped out before a baseline weight was obtained; data from 21 individuals were analysed. Mean weight loss in kilogram was 4.3 (SD 4.8) at 6 months and 4.9 (SD 5.8) at 12 months. Mean per cent body weight changes were 4.5 (SD 5.0) at 6 months and 5.2 (SD 6.0) at 12 months; 8/21 individuals (38%) achieved ≥5% wt loss at 12 months. Mean attendance was 10.3/16 weekly sessions and 3.4/7 biweekly or monthly sessions. Among interviewees (n=14), three factors facilitated VLCD adherence: (1) enjoyment of low-carbohydrate foods, (2) diminished hunger and cravings and (3) health benefits beyond weight loss. Three factors hindered VLCD adherence: (1) enjoyment of high-carbohydrate foods, (2) lack of social support and (3) difficulty preplanning meals. CONCLUSIONS: An LC-DPP is feasible, acceptable and may be an effective option to help individuals with pre-diabetes to lose weight. Data from this pilot will be used to plan a fully powered randomised controlled trial of weight loss among NDPP versus LC-DPP participants. TRIAL REGISTRATION NUMBER: NCT03258918.

Comparison of a gratitude-based and cognitive restructuring intervention for body dissatisfaction and dysfunctional eating behavior in college women.

Researchers have investigated the efficacy of a gratitude intervention for decreasing body dissatisfaction (BD) in an internet treatment-seeking sample and demonstrated it worked equally well to decrease BD as cognitive restructuring. We extend this research by testing the efficacy of a gratitude intervention on BD, along with common sequelae of BD: dysfunctional eating, negative mood, and depressive symptoms. Females were randomly assigned to Gratitude, Cognitive Restructuring, or Control conditions. Pre- to post-intervention period comparisons found the gratitude intervention to perform better than the other conditions at increasing body esteem, decreasing BD, reducing dysfunctional eating, and reducing depressive symptoms.

Influence of adipose tissue mass on DXA-derived lean soft tissue mass in middle-aged and older women.

The purpose of this study was to examine the influence of fat-free adipose tissue mass (FFAT) on association between dual-energy X-ray absorptiometry (DXA)-derived lean soft tissue mass and skeletal muscle mass (TMM). Forty-one middle-aged and older women were recruited for this study. Percent body fat, total and appendicular fat mass (tFM and aFM, respectively), and total and appendicular lean soft tissue mass (tLM and aLM, respectively) were measured using a DXA. FFAT was calculated based on the methods of a previous study. TMM was estimated from the ultrasound-derived prediction equation. The subjects were separated into three groups based on DXA-determined percent fat: low (n = 12, <25 %), middle (n = 15, ≥25 and <35 %), and high (n = 14, ≥35 %). DXA-derived aLM was greater in high than in middle or low, although ultrasound-estimated TMM was similar among the three groups. There was a strong correlation between aLM and TMM (r = 0.905, p < 0.001). The difference between aLM and TMM was correlated (p < 0.001) with aFM (r = 0.599) and tFM (r = 0.587). After adjusting for FFAT, aLM minus appendicular FFAT was similar among the three groups. aLM minus appendicular FFAT was strongly associated with TMM (r = 0.912, p < 0.001). Our results suggest that DXA-derived aLM accurately predicts TMM when subjects have moderate or lower adipose tissue mass. However, FFAT may falsely inflate the DXA-derived aLM measurement in individuals with a relatively high amount of adipose tissue mass (>35 % of body fat). Therefore, in this population, it is advisable to use DXA-derived aLM minus FFAT when evaluating age-related loss of skeletal muscle mass.

Rowing performance, body composition, and bone mineral density outcomes in college-level rowers after a season of concurrent training.

PURPOSE: To assess changes in body composition, lumbar-spine bone mineral density (BMD), and rowing performance in college-level rowers over a competition season. METHODS: Eleven Division I college rowers (mean ± SD 21.4 ± 3.7 y) completed 6 testing sessions throughout the course of their competition season. Testing included measurements of fat mass, bone-free lean mass (BFLM), body fat (%BF), lumbar-spine BMD, and 2000-m time-trial performance. After preseason testing, rowers participated in a periodized training program, with the addition of resistance training to the traditional aerobic-training program. RESULTS: Significant (P < .05) improvements in %BF, total mass, and BFLM were observed at midseason and postseason compared with preseason. Neither lumbar-spine BMD nor BMC significantly changed over the competitive season (P > .05). Finally, rowing performance (as measured by 2000-m time and average watts achieved) significantly improved at midseason and postseason compared with preseason. CONCLUSION: Our results highlight the efficacy of a seasonal concurrent training program serving to improve body composition and rowing performance, as measured by 2000-m times and average watts, among college-level rowers. Our findings offer practical applications for coaches and athletes looking to design a concurrent strength and aerobic training program to improve rowing performance across a season.

Site-specific thigh muscle loss as an independent phenomenon for age-related muscle loss in middle-aged and older men and women.

The purpose of this study was to examine the relationships between dual-energy X-ray absorptiometry (DXA)-determined appendicular lean mass (aLM) and ultrasound-measured thigh muscle thickness (MTH) ratio and between aLM or thigh MTH ratio and zigzag walking performance. Eighty-one middle-aged and older adults (41 men and 40 women) aged 50 to 74 years volunteered for the study. Approximately two thirds of the subjects (34 men and 17 women) carried out regular sports activity (at least >2 times a week) including running and cycling exercise. MTH was measured using B-mode ultrasound at two sites on the anterior (A50) and posterior (P50) aspects of the mid-thigh. A50:P50 MTH ratio was calculated to evaluate site-specific thigh muscle loss. aLM and percent body fat were also determined using a DXA. Men had lower body fat and higher aLM than women. Anterior and posterior thigh MTH as well as A50:P50 MTH ratio was higher in men than in women. Zigzag walking time was faster in men than in women. Anterior and posterior thigh MTH was positively (p < 0.001) correlated to aLM and aLM index in men and women. However, A50:P50 MTH ratio was not significantly correlated with aLM and aLM index in both sexes. There was no significant correlation between aLM index and zigzag walking time in men and women. A50:P50 MTH ratio was inversely (p < 0.05) correlated to zigzag walking time in both men and women. Our results suggest that thigh MTH ratio is independent of age-related muscle mass loss detected by aLM.

Skeletal muscle mass, bone mineral density, and walking performance in masters cyclists.

Exercise mode and intensity/duration are important factors for influencing muscle morphology and function as well as bone. However, it is unknown whether masters cyclists who undergo regular moderate- to high-intensity exercise maintain lower-body skeletal muscle mass (SM) and function and bone health when compared with young adults. The purpose of this study was to compare SM, areal bone mineral density (aBMD), and gait performance between masters cyclists and young adults. Fourteen male masters cyclists (aged 53-71 years) and 13 moderately active young men (aged 20-30 years, exercising less than twice a week) volunteered. The masters cyclists were all training actively (four to five times per week, ∼200 miles per week) for on average the last 17 years (range 7-38 years). Thigh SM was estimated from an ultrasound-derived prediction equation using muscle thickness (MTH). Appendicular lean mass (aLM) and aBMD were also estimated using dual-energy X-ray absorptiometry. There were no significant differences (p<0.05) in thigh SM, anterior and posterior thigh MTH ratio, or aLM between masters cyclists and young men. Maximum straight and zigzag walking times were also similar between groups. Lumbar spine (L1-L4) aBMD was not different between groups, but femoral neck aBMD was lower (p<0.05) in the cyclists than in the young men. Our results suggest that appendicular as well as site-specific thigh muscle loss with aging were not observed in masters cyclists. This maintenance of muscle mass in masters cyclists may preserve walking performance to similar levels as moderately active young adults. However, long-term cycling does not preserve femoral neck aBMD.

Are serum hepcidin levels chronically elevated in collegiate female distance runners?

The prevalence of iron deficiency tends to be higher in athletic populations, especially among endurance-trained females. Recent studies have provided evidence that the iron-regulating hormone hepcidin is transiently increased with acute exercise and suggest that this may contribute to iron deficiency anemia in athletes. The purpose of this study was to determine whether resting serum hepcidin is significantly elevated in highly trained female distance runners compared with a low exercise control group. Due to the importance of the monocyte in the process of iron recycling, monocyte expression of hepcidin was also measured. A single fasted blood sample was collected midseason from twenty female distance runners averaging 81.9 ± 14.2 km of running per week. Ten age-, gender-, and BMI-matched low-exercise control subjects provided samples during the same period using identical collection procedures. There was no difference between the runners (RUN) and control subjects (CON) for serum hepcidin levels (p = .159). In addition, monocyte hepcidin gene expression was not different between the two groups (p = .635). Furthermore, no relationship between weekly training volume and serum hepcidin concentration was evident among the trained runners. The results suggest that hepcidin is not chronically elevated with sustained training in competitive collegiate runners. This is an important finding because the current clinical conditions that link hepcidin to anemia include a sustained elevation in serum hepcidin. Nevertheless, additional studies are needed to determine the clinical relevance of the well-documented, transient rise in hepcidin that follows acute sessions of exercise.