John R Speakman
Dados Biográficos
| ID | 178024 |
|---|---|
| NOME | John R Speakman |
| PRENOMES | John R |
| SOBRENOME | Speakman |
| ASSINATURA | SPEAKMAN J R |
| AFILIAÇÕES | University of Aberdeen |
| ORCID | 0000-0002-2457-1823 |
| VERIFICADO | Sim |
| TOTAL DE OBRAS | 11 |
| TOTAL DE CITAÇÕES | 5 |
| TOTAL COMO AUTOR | 11 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2009 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2024 |
| ÍNDICE H | 1 |
Validation of predictive equations to estimate resting metabolic rate of females and males across different activity levels
Objectives Using equations to predict resting metabolic rate (RMR) has yielded different degrees of validity, particularly when sex and different physical activity levels were considered. Therefore, the purpose of the present study was to determine the validity of several different predictive equations to estimate RMR in female and male adults with varying physical activity levels. Method We measured the RMR of 50 adults (26 females and 24 males)…
Not feeling the heat? Effects of dietary protein on satiation and satiety in mice are not due to its impact on body temperature
Dietary protein modulates food intake (FI) via unclear mechanism(s). One possibility is that higher protein leads to greater post-ingestive heat production (Specific dynamic action: SDA) leading to earlier meal termination (increased satiation), and inhibition of further intake (increased satiety). The influence of dietary protein on feeding behaviour in C57BL/6J mice was tested using an automated FI monitoring system (BioDAQ), simultaneous to bo…
Reply to G Taubes, MI Friedman, and V Torres-Carot et al
Variability in energy expenditure is much greater in males than females
In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male v…
Different impacts of resources on opposite sex ratings of physical attractiveness by males and females
Sex- And Age-Related Mortality Profiles During Famine
During famines females generally have a mortality advantage relative to males, and the highest levels of mortality occur in the very young and the elderly. One popular hypothesis is that the sex differential in mortality may reflect the greater body fatness combined with lower metabolism of females, which may also underpin the age-related patterns of mortality among adults. This study evaluated the ‘body fat’ hypothesis using a previously publish…
Free-living physical activity and energy expenditure of rural children and adolescents in the Nandi region of Kenya
High physical activity levels were associated with much higher levels of energy expenditure than observed in Western societies. These results oppose the concept of physical activity being stable and constrained in humans
Energetic consequences of seasonal breeding in female Japanese macaques ( Macaca fuscata )
Japanese macaques inhabit a relatively cold environment and females of this species could have developed strategies of energy economy to face the sometimes‐harsh seasonal conditions of temperate climates, as well as reproductive costs, and thus regulate their energy balance. Here, we explore the relationship between nutritional status, body composition, seasonality, and reproductive status using isotope‐labeled water, anthropometric measurements,…
Evaluating energy intake measurement in free-living subjects
Objective To nutritionally analyse mean energy intake (EI) from different 3 d intervals within a 7 d recording period and to evaluate the seasonal effect on energy and nutrient intake. Design Cross-sectional study of dietary intake collected with 7 d food diaries. Setting Aberdeen, north-east Scotland, UK, between 2002 and 2004. Subjects Participants from two long-term trials were pooled. These trials, investigating genetic and environmental infl…
Thrifty genes and drifty genes. The evolutionary context of the obesity epidemic
Do Highly Modified Landscapes Favour Generalists at the Expense of Specialists? An Example using Woodland Birds
Demands on land use in heavily populated landscapes create mosaic structures where semi-natural habitat patches are generally small and dominated by edges. Small patches are also more exposed and thus more vulnerable to adverse weather and potential effects of climate change. These conditions may be less problematic for generalist species than for specialists. Using insectivorous woodland birds (great tits and blue tits) as an example, we demonst…
Variability in energy expenditure is much greater in males than females
In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male v…
Energetic consequences of seasonal breeding in female Japanese macaques ( Macaca fuscata )
Japanese macaques inhabit a relatively cold environment and females of this species could have developed strategies of energy economy to face the sometimes‐harsh seasonal conditions of temperate climates, as well as reproductive costs, and thus regulate their energy balance. Here, we explore the relationship between nutritional status, body composition, seasonality, and reproductive status using isotope‐labeled water, anthropometric measurements,…
Do Highly Modified Landscapes Favour Generalists at the Expense of Specialists? An Example using Woodland Birds
Demands on land use in heavily populated landscapes create mosaic structures where semi-natural habitat patches are generally small and dominated by edges. Small patches are also more exposed and thus more vulnerable to adverse weather and potential effects of climate change. These conditions may be less problematic for generalist species than for specialists. Using insectivorous woodland birds (great tits and blue tits) as an example, we demonst…
Do Highly Modified Landscapes Favour Generalists at the Expense of Specialists? An Example using Woodland Birds
Demands on land use in heavily populated landscapes create mosaic structures where semi-natural habitat patches are generally small and dominated by edges. Small patches are also more exposed and thus more vulnerable to adverse weather and potential effects of climate change. These conditions may be less problematic for generalist species than for specialists. Using insectivorous woodland birds (great tits and blue tits) as an example, we demonst…
Evaluating energy intake measurement in free-living subjects
Objective To nutritionally analyse mean energy intake (EI) from different 3 d intervals within a 7 d recording period and to evaluate the seasonal effect on energy and nutrient intake. Design Cross-sectional study of dietary intake collected with 7 d food diaries. Setting Aberdeen, north-east Scotland, UK, between 2002 and 2004. Subjects Participants from two long-term trials were pooled. These trials, investigating genetic and environmental infl…
Thrifty genes and drifty genes. The evolutionary context of the obesity epidemic
Energetic consequences of seasonal breeding in female Japanese macaques ( Macaca fuscata )
Japanese macaques inhabit a relatively cold environment and females of this species could have developed strategies of energy economy to face the sometimes‐harsh seasonal conditions of temperate climates, as well as reproductive costs, and thus regulate their energy balance. Here, we explore the relationship between nutritional status, body composition, seasonality, and reproductive status using isotope‐labeled water, anthropometric measurements,…
Sex- And Age-Related Mortality Profiles During Famine
During famines females generally have a mortality advantage relative to males, and the highest levels of mortality occur in the very young and the elderly. One popular hypothesis is that the sex differential in mortality may reflect the greater body fatness combined with lower metabolism of females, which may also underpin the age-related patterns of mortality among adults. This study evaluated the ‘body fat’ hypothesis using a previously publish…
Free-living physical activity and energy expenditure of rural children and adolescents in the Nandi region of Kenya
High physical activity levels were associated with much higher levels of energy expenditure than observed in Western societies. These results oppose the concept of physical activity being stable and constrained in humans
Different impacts of resources on opposite sex ratings of physical attractiveness by males and females
Reply to G Taubes, MI Friedman, and V Torres-Carot et al
Variability in energy expenditure is much greater in males than females
In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male v…
Validation of predictive equations to estimate resting metabolic rate of females and males across different activity levels
Objectives Using equations to predict resting metabolic rate (RMR) has yielded different degrees of validity, particularly when sex and different physical activity levels were considered. Therefore, the purpose of the present study was to determine the validity of several different predictive equations to estimate RMR in female and male adults with varying physical activity levels. Method We measured the RMR of 50 adults (26 females and 24 males)…
Not feeling the heat? Effects of dietary protein on satiation and satiety in mice are not due to its impact on body temperature
Dietary protein modulates food intake (FI) via unclear mechanism(s). One possibility is that higher protein leads to greater post-ingestive heat production (Specific dynamic action: SDA) leading to earlier meal termination (increased satiation), and inhibition of further intake (increased satiety). The influence of dietary protein on feeding behaviour in C57BL/6J mice was tested using an automated FI monitoring system (BioDAQ), simultaneous to bo…
Biology (9 obras) · Demography (5 obras) · Endocrinology (5 obras) · Medicine (4 obras) · Diet and metabolism studies (3 obras) · Animal Behavior and Reproduction (2 obras) · Animal science (2 obras) · Basal metabolic rate (2 obras) · Birth, Development, and Health (2 obras) · Body Composition Measurement Techniques (2 obras)