The value of publicly engaged podcasting in human biology.

Podcasting about science may be popular, but does it motivate engagement? The Human Biology Association and American Journal of Human Biology (AJHB) cosponsor a podcast that highlights recent articles. We hypothesized that AJHB articles discussed on the podcast (n = 42) receive more online views than other articles from the same issues. We used Student's t-tests to compare mean article views and found podcasted articles received more views, but the difference was not significant.

Indication of mixed glucose and fatty acid use by inferred brown adipose tissue activity in Samoans.

Objectives: Despite the growing rates of global obesity and the known positive associations between brown adipose tissue (BAT) and cardiovascular health, little is known about the metabolic effects of BAT activity in Samoans, a population at high risk of obesity and type II diabetes. Here we assessed the potential effects of inferred BAT activity on metabolic health markers in Samoan adults exposed to mild cold.

Methods: Using point-of-care finger prick technology we measured fasting glucose, total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) levels before and after 30 min of cold exposure among 61 individuals (38 females, 23 males, ages 31-54) from 'Upolu Island, Samoa.

When the cold gets under your skin: Evidence for brown adipose tissue activity in Samoan adults.

Objectives: Brown adipose tissue (BAT) is a heat-producing organ aiding nonshivering thermogenesis (NST) during cold stress. Due to its potential cold-adaptive role BAT has been predominantly studied in cold and temperate climate populations, but not among warm-climate adults. This work explores if BAT activity can be inferred in Samoans.

Total Energy Expenditure and Nutritional Intake in Continuous Multiday Ultramarathon Events.

Continuous multiday ultramarathon competitions are increasingly popular and impose extreme energetic and nutritional demands on competitors. However, few data have been published on energy expenditure during these events. Here, we report doubly labeled water-derived measures of total energy expenditure (in kilocalories per day) and estimated physical activity level (PAL: total energy expenditure/basal metabolic rate) collected from five elite and subelite finishers (four males and one female, age 34.

Estimated energetic demands of thermoregulation during ancient canoe passages from Tahiti to Hawaii and New Zealand, a simulation analysis.

Prehistoric colonization of East Polynesia represents the last and most extensive of human migrations into regions previously uninhabited. Although much of East Polynesia is tropical, the southern third, dominated by New Zealand-by far the largest Polynesian landmass-ranges from a warm- to cool-temperate climate with some islands extending into the Subantarctic. The substantial latitudinal variation implies questions about biocultural adaptations of tropical people to conditions in which most of their familiar resources were absent and their agriculture marginal.

To the extreme! How biological anthropology can inform exercise physiology in extreme environments.

The fields of biological anthropology and exercise physiology are closely related and can provide mutually beneficial insights into human performance. These fields often use similar methods and are both interested in how humans function, perform, and respond in extreme environments. However, these two fields have different perspectives, ask different questions, and work within different theoretical frameworks and timescales.

Human cold adaptation: An unfinished agenda v2.0.

Background: Research on human extreme cold climate adaptations has benefitted from a recent resurgence since Ted Steegmann laid out his Human Cold Adaptation Agenda in 2007. Human biologists have drastically expanded our knowledge in this area during the last 15 years, but we still have a great deal more work to do to fulfill the cold climate adaptation agenda.

Methods: Here, I follow Steegmann's example by providing a review of cold climate adaptations and setting forth a new, expanded agenda.

"I feel terrible and need to exercise to find any sort of joy": What COVID stay-at-home orders tell us about exercise as vitality politics and entertainment in the United States.

During COVID-19 stay-at-home orders (SaHOs), people faced drastic shifts in their work and home lives. These shifts, in combination with the temporary closure of gyms and fitness centers, led to exercise-routine disruption. We conducted a survey to assess how people were affected by SaHOs in terms of exercise-routine change, feelings about exercise, perceived physical and mental health, as well as exercise-routine plans once SaHOs were lifted.

The impact of winter warming and more frequent icing events on reindeer herder occupational safety, health, and wellbeing.

Background: Northern Finland, like the rest of the Arctic, has experienced increases in mean annual temperature, the number of winter rains, the number of thaw-freeze days, the number of extremely warm weather events, and a shortened snow season. These changes have produced numerous problems for reindeer herders whose livelihoods rely on a healthy ecosystem with predictable weather patterns.

Methods: We performed a scoping literature review to assess how climate change induced extreme weather has negatively impacted reindeer herding as well as the health and wellbeing of reindeer herders.

Commentary-fat but fit…and cold? Potential evolutionary and environmental drivers of metabolically healthy obesity.

As global obesity rates continue to rise, it is important to understand the origin, role and range of human variation of body mass index (BMI) in assessing health and healthcare. A growing body of evidence suggests that BMI is a poor indicator of health across populations, and that there may be a metabolically healthy obese phenotype. Here, we review the reasons why BMI is an inadequate tool for assessing cardiometabolic health.

Brown adipose tissue thermogenesis among a small sample of reindeer herders from sub-Arctic Finland.

Introduction: Interest in human physiological responses to cold stress have seen a resurgence in recent years with a focus on brown adipose tissue (BAT), a mitochondria dense fat specialized for heat production. However, a majority of the work examining BAT has been conducted among temperate climate populations.

Methods: To expand our understanding of BAT thermogenesis in a cold climate population, we measured, using indirect calorimetry and thermal imaging, metabolic rate and body surface temperatures of BAT-positive and BAT-negative regions at room temperature, and mild cold exposure of resting participants from a small sample of reindeer herders (N = 22, 6 females) from sub-Arctic Finland.

No association of BMI and body adiposity with cardiometabolic biomarkers among a small sample of reindeer herders of sub-Arctic Finland.

The rising global obesity rate is alarming due to its real health and socioeconomic consequences. Finland, like other circumpolar regions, is also experiencing a rise in obesity . Here we assess BMI, body adiposity, and measures of cardiometabolic health among a small population of reindeer herders in sub-Arctic Finland.

Weather permitting: Increased seasonal efficiency of nonshivering thermogenesis through brown adipose tissue activation in the winter.

Objectives: We investigated seasonal changes in brown adipose tissue (BAT) activation and metabolism in a temperate-climate Albany, NY population.

Methods: Data were collected among 58 participants (21 males, 37 females, ages: 18-51) in the summer and 59 participants (23 males, 36 females, ages: 18-63) in the winter in Albany, New York. BAT activity was inferred by comparing metabolic rate, heat dissipation in the supraclavicular area, and respiratory quotient at room temperature and cold exposure.

Feasibility of using infrared thermal imaging to examine brown adipose tissue in infants aged 18 to 25 months.

Background: Recent studies in adults indicate that cold-induced temperature change of supraclavicular skin corresponds with brown adipose tissue (BAT) thermogenesis.

Aim: This study examined the feasibility of using thermography to assess temperature changes in infants aged 18-25 months after mild cooling. Further, this study sought to evaluate whether cold exposure induces a thermal response suggestive of BAT activity underlying the supraclavicular region.

Demystifying mentorship: Tips for successfully navigating the mentor-mentee journey.

Background: Quality mentorship is crucial for long-term success in academia and overall job satisfaction. Unfortunately, formal mentorship training is lacking, and there is little recourse for failed mentor-mentee relationships.

Methods: We performed a literature review to understand the current state of mentorship research with a focus on: (1) what mentorship is and why it is important for success; (2) establishing mentor-mentee relationships; and (3) the role of diversity, equity, and inclusion.

Reindeer herders from subarctic Finland exhibit high total energy expenditure and low energy intake during the autumn herd roundup.

Objective: High levels of total energy expenditure (TEE, kcal/day) have been documented among numerous human populations such as tropical climate horticulturalists and high-altitude agriculturalists. However, less work has been conducted among highly physically active cold climate populations.

Methods: In October 2018, TEE was measured using the doubly labeled water (TEE , N = 10) and flex-heart rate methods (TEE , N = 24) for 6-14 days among reindeer herders (20-62 years) in northern Finland during an especially physically demanding, but not seasonally representative, period of the year for herders-the annual reindeer herd roundup.

#Hackademics: Hacks toward success in academia.

Objective: The Sausage of Science is a podcast for the Human Biology Association and the American Journal of Human Biology through which we introduced a special series called #Hackademics. The podcast was initially used to highlight the scholarship and humanity of fellow human biologists through interviews about "how the sausage is made" in research-that is, the nuts and bolts that go into our publications. However, we soon realized there is much more a weekly podcast can do to help colleagues in our interrelated fields.

Sex differences and shifts in body composition, physical activity, and total energy expenditure across a 3-month expedition.

Objectives: An energetically demanding environment like a wilderness expedition can lead to potent stressors on human physiology and homeostatic balance causing shifts in energy expenditure and body composition. These shifts likely have consequences on overall health and performance and may potentially differ by sex. It is therefore critical to understand the potential differential body composition and energy expenditure changes in response to a novel and challenging environment in both males and female bodies.

Between a rock and a cold place: Neanderthal biocultural cold adaptations.

A large body of work focuses on the unique aspects of Neanderthal anatomy, inferred physiology, and behavior to test the assumption that Neanderthals were hyper-adapted to living in cold environments. This research has expanded over the years to include previously unexplored and potentially adaptive features such as brown adipose tissue and fire-usage. Here we review the current state of knowledge of Neanderthal cold adaptations along morphological, physiological, and behavioral lines.

Elevated resting metabolic rates among female, but not male, reindeer herders from subarctic Finland.

Objective: Elevated resting metabolic rates (RMR, kcal/day) are a well-established mechanism for maintaining core body temperature among cold climate populations. A high degree of interindividual variation has recently been noted among circumpolar populations. To further examine RMR variability, we investigated anthropometric and metabolic differences among reindeer herders from subarctic Finland.

Extreme events reveal an alimentary limit on sustained maximal human energy expenditure.

The limits on maximum sustained energy expenditure are unclear but are of interest because they constrain reproduction, thermoregulation, and physical activity. Here, we show that sustained expenditure in humans, measured as maximum sustained metabolic scope (SusMS), is a function of event duration. We compiled measurements of total energy expenditure (TEE) and basal metabolic rate (BMR) from human endurance events and added new data from adults running ~250 km/week for 20 weeks in a transcontinental race.

Sustained high levels of physical activity lead to improved performance among "Race Across the USA" athletes.

Objective: To investigate physiological and performance adaptations associated with extremely high daily sustained physical activity levels, we followed six runners participating in the 2015 Race Across the USA. Participants completed over 42.2 km a day for 140 days, covering nearly 5,000 km.