Commentary: Is Wearable Fitness Technology a Medically Approved Device? Yes and No.

Wearable technologies, i.e., activity trackers and fitness watches, are extremely popular and have been increasingly integrated into medical research and clinical practice. To assist in optimizing health, wellness, or medical care, these devices require collaboration between researchers, healthcare providers, and wearable technology companies in order to clarify their clinical capabilities and educate consumers on the utilities and limitations of the wide-ranging wearable devices. Interestingly, activity trackers and fitness watches often track both health/wellness and medical information within the same device. In this commentary, we will focus our discussions regarding wearable technology on (1) defining and explaining the technical differences between tracking health, wellness, and medical information; (2) providing examples of health and wellness compared to medical tracking; (3) describing the potential medical benefits of wearable technology and its applications in clinical populations; and (4) elucidating the potential risks of wearable technology. We conclude that while wearable devices are powerful and informative tools, further research is needed to improve its clinical applications.

Examining the Role of Physical Activity Interventions in Modulating Androgens and Cardiovascular Health in Postmenopausal Women: A Narrative Review.

A growing body of literature has examined the role of physical activity (PA) in modifying the effects of estrogen withdrawal on cardiovascular health in postmenopausal women, but the impact of PA on androgens is less clear. Changes in androgen concentrations following regular PA may improve cardiovascular health. This narrative review summarizes the literature assessing the impact of PA interventions on androgens in postmenopausal women. The association between changes in androgen concentrations and cardiovascular health following PA programs is also examined. Randomized controlled trials were included if they (i) implemented a PA program of any type and duration in postmenopausal women and (ii) measured changes in androgen concentrations. Following PA interventions, no changes in androstenedione, conflicting changes in dehydroepiandrosterone/dehydroepiandrosterone-sulfate, and increases in sex hormone-binding globulin concentrations were found. Total testosterone decreased following aerobic PA but increased after resistance training. Most aerobic PA interventions led to reductions in free testosterone. A combination of caloric restriction and/or fat loss enhanced the influence of PA on most androgens. Evidence exploring the relationship between changes in androgens and cardiovascular health indicators was scarce and inconsistent. PA has shown promise in modifying the concentrations of some androgens (free and total testosterone, sex hormone-binding globulin), and remains a well-known beneficial adjuvant option for postmenopausal women to manage their cardiovascular health. Fat loss influences the effect of PA on androgens, but the synergistic role of PA and androgens on cardiovascular health merits further examination. Many research gaps remain regarding the relationship between PA, androgens, and cardiovascular disease in postmenopausal women.

Un nombre croissant de publications ont examiné le rôle de l'activité physique (AP) pour contrer les effets de la privation en œstrogènes sur la santé cardiovasculaire des femmes ménopausées, mais les effets de l'AP sur les androgènes sont moins évidents. Les variations des taux d'androgènes associées à l'AP régulière pourraient améliorer la santé cardiovasculaire. Cette revue narrative résume des articles ayant évalué les répercussions des interventions fondées sur l'AP sur les taux d'androgènes chez les femmes ménopausées. Le lien entre la santé cardiovasculaire et les variations des taux d'androgènes consécutives à des programmes d'AP a également été examiné. Des essais contrôlés randomisés étaient inclus s'ils comprenaient (i) la mise en œuvre d'un programme d'AP quel qu'en soit le type ou la durée chez des femmes ménopausées et (ii) la mesure des variations des taux d'androgènes. Aucune variation des taux d'androstènedione n'a été observée après des interventions fondées sur l'AP. Toutefois, des variations conflictuelles des taux de déhydroépiandrostérone et de sulfate de déhydroépiandrostérone et des hausses des taux de la globuline liant les hormones sexuelles ont été observés. Le taux de testostérone totale a diminué après l'AP en aérobie, mais a augmenté après l'entraînement contre résistance. La plupart des interventions fondées sur l'AP en aérobie ont entraîné des réductions du taux de testostérone libre. En association avec la restriction calorique et/ou une perte de graisse corporelle, l'AP exerce une influence accrue sur la plupart des androgènes. Les données probantes explorant le lien entre les variations des taux d'androgènes et les indicateurs de santé cardiovasculaire étaient rares et contradictoires. L'AP s'est révélée prometteuse pour ce qui est de modifier les taux de certains androgènes (testostérone libre et testostérone totale, globuline liant les hormones sexuelles); elle demeure une option adjuvante bénéfique bien connue pour aider les femmes ménopausées à prendre en charge leur santé cardiovasculaire. La perte de graisse corporelle influe sur les effets de l'AP sur les androgènes, mais le rôle synergique de l'AP et des androgènes sur la santé cardiovasculaire mérite un examen plus approfondi. De nombreuses lacunes subsistent quant à la recherche d'un lien entre l'AP, les androgènes et les maladies cardiovasculaires chez les femmes ménopausées.

Perceived Exertion during Moderate and Vigorous Physical Activity While Mask Wearing: A Quantitative and Qualitative Pilot Study.

There is limited research examining the perception of exertion during exercise while wearing a facemask. The current study examined if mask usage during moderate or vigorous physical activity (MVPA) changed the self-reported perception of exertion. Seventy-two adults (18 years and older) who were physically active before the COVID-19 pandemic completed a questionnaire that assessed exercise habits and perceptions of mask wearing during MVPA. Participants reported their ratings of perceived exertion (RPE, on a scale of 1−10) while exercising. Wearing a mask resulted in higher RPE vs. no mask during both vigorous (8.4 ± 0.2 vs. 7.4 ± 0.1; p < 0.001) and moderate PA (6.6 ± 0.2 vs. 5.6 ± 0.2; p < 0.001). Qualitative analysis revealed mostly negative perceptions of exercising while wearing a mask, including respiratory issues, detriments to cardiovascular endurance, and general discomfort. A total of 40% of participants reported that they stopped exercising in an indoor/public setting because of a mask mandate in their region. Participants reported participating in less vigorous PA (4.7 ± 0.4 vs. 4.0 ± 0.4 h/week; p = 0.046), but not less moderate PA (3.3 ± 0.3 vs. 3.0 ± 0.3 h/week; p = 0.443) pre vs. during the pandemic. Our study suggests that facemask usage during MVPA causes an increase in RPE and may be one reason for a decrease in vigorous PA during the COVID-19 pandemic.

Impact of Web-Based Meeting Platform Usage on Overall Well-Being among Higher Education Employees.

During the ongoing global pandemic, faculty, staff and administrators at colleges and universities experienced an increase in meetings using web-based platforms. Challenges were identified related to the changes from face-to-face to web-based meetings, including internet connectivity, inadequate technology and distractions in the online environment, which led to questions about how meetings that use web-based platforms may contribute to overall stress and well-being during the pandemic. The research related to the use of web-based meeting platforms is limited. However, some anecdotal evidence suggests that impacts from web-based meeting platforms could include frustration, sleep issues and fatigue, which contribute to overall well-being. The purpose of this study was to determine if a relationship exists between a number of potentially related web-based meeting factors including the frequency and length of the meetings and comfort level with the platform and overall well-being. This study involved (N = 164) male, female and nonbinary participants over 18 years of age who worked as tenured, tenure-track, or nontenure track faculty, staff and administrators at colleges/universities in the United States during the global pandemic. The participants were recruited via both social media and email and were provided with a link to the survey tool, which included demographic and web-based meeting questions (e.g., frequency, length, and comfort) along with scales to measure perceived stress, subjective well-being, mental fatigue and sleep quality. The current study did not find a relationship between the frequency of meetings and overall well-being (p = 0.294). However, statistically significant relationships were found between meeting length and overall well-being (p = 0.003) and between comfort with the web-based meeting platform and overall well-being (p = 0.030). Based on the findings of this study, meeting organizers may consider scheduling meetings for less than two hours and providing training to ensure participants are proficient in the web-based meeting platform in order to support overall well-being.

Randomised controlled trial of the effects of increased energy intake on menstrual recovery in exercising women with menstrual disturbances: the 'REFUEL' study.

STUDY QUESTION: Does increased daily energy intake lead to menstrual recovery in exercising women with oligomenorrhoea (Oligo) or amenorrhoea (Amen)? SUMMARY ANSWER: A modest increase in daily energy intake (330 ± 65 kcal/day; 18 ± 4%) is sufficient to induce menstrual recovery in exercising women with Oligo/Amen. WHAT IS KNOWN ALREADY: Optimal energy availability is critical for normal reproductive function, but the magnitude of increased energy intake necessary for menstrual recovery in exercising women, along with the associated metabolic changes, is not known. STUDY DESIGN, SIZE, DURATION: The REFUEL study (trial # NCT00392873) is the first randomised controlled trial to assess the effectiveness of 12 months of increased energy intake on menstrual function in 76 exercising women with menstrual disturbances. Participants were randomised (block method) to increase energy intake 20-40% above baseline energy needs (Oligo/Amen + Cal, n = 40) or maintain energy intake (Oligo/Amen Control, n = 36). The study was performed from 2006 to 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were Amen and Oligo exercising women (age = 21.0 ± 0.3 years, BMI = 20.8 ± 0.2 kg/m2, body fat = 24.7 ± 0.6%) recruited from two universities. Detailed assessment of menstrual function was performed using logs and measures of daily urinary ovarian steroids. Body composition and metabolic outcomes were assessed every 3 months. MAIN RESULTS AND THE ROLE OF CHANCE: Using an intent-to-treat analysis, the Oligo/Amen + Cal group was more likely to experience menses during the intervention than the Oligo/Amen Control group (P = 0.002; hazard ratio [CI] = 1.91 [1.27, 2.89]). In the intent-to-treat analysis, the Oligo/Amen + Cal group demonstrated a greater increase in energy intake, body weight, percent body fat and total triiodothyronine (TT3) compared to the Oligo/Amen Control group (P < 0.05). In a subgroup analysis where n = 22 participants were excluded (ambiguous baseline menstrual cycle, insufficient time in intervention for menstrual recovery classification), 64% of the Oligo/Amen + Cal group exhibited improved menstrual function compared with 19% in the Oligo/Amen Control group (χ2, P = 0.001). LIMITATIONS, REASONS FOR CAUTION: While we had a greater than expected dropout rate for the 12-month intervention, it was comparable to other shorter interventions of 3-6 months in duration. Menstrual recovery defined herein does not account for quality of recovery. WIDER IMPLICATIONS OF THE FINDINGS: Expanding upon findings in shorter, non-randomised studies, a modest increase in daily energy intake (330 ± 65 kcal/day; 18 ± 4%) is sufficient to induce menstrual recovery in exercising women with Oligo/Amen. Improved metabolism, as demonstrated by a modest increase in body weight (4.9%), percent body fat (13%) and TT3 (16%), was associated with menstrual recovery. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the U.S. Department of Defense: U.S. Army Medical Research and Material Command (Grant PR054531). Additional research assistance provided by the Penn State Clinical Research Center was supported by the National Center for Advancing Translation Sciences, National Institutes of Health, through Grant UL1 TR002014. M.P.O. was supported in part by the Loretta Anne Rogers Chair in Eating Disorders at University of Toronto and University Health Network. All authors report no conflict of interest. TRIAL REGISTRATION NUMBER: NCT00392873. TRIAL REGISTRATION DATE: October 2006. DATE OF FIRST PATIENT'S ENROLMENT: September 2006.

Commentary: Physiological and Psychological Impact of Face Mask Usage during the COVID-19 Pandemic.

In this commentary, we discuss the physiological effects of wearing masks for prolonged periods of time, including special considerations, such as mask wearing among those who engage in exercise training, and concerns for individuals with pre-existing chronic diseases. In healthy populations, wearing a mask does not appear to cause any harmful physiological alterations, and the potentially life-saving benefits of wearing face masks seem to outweigh the documented discomforts (e.g. headaches). However, there continues to be controversy over mask wearing in the United States, even though wearing a mask appears to have only minor physiological drawbacks. While there are minimal physiological impacts on wearing a mask, theoretical evidence suggests that there may be consequential psychological impacts of mask wearing on the basic psychological needs of competence, autonomy, and relatedness. These psychological impacts may contribute to the controversy associated with wearing masks during the COVID-19 pandemic in the United States. After we discuss the physiological impacts of mask wearing, we will discuss psychological effects associated with wearing masks during the COVID-19 pandemic.

Sedentary Behavior and the Use of Wearable Technology: An Editorial.

Globally, we continue to face a mounting issue of obesity combined with inactivity; sedentary behaviour is independently associated with poor health outcomes including disease and mortality. As such, exploring ways to try to reduce sedentary behaviour and decrease the risk of diseases is an important area of consideration. The role of wearable technology, such as fitness trackers, to encourage and subsequently increase physical activity is relatively well documented. These devices have been successful at encouraging populations to increase daily activity levels. While time being sedentary is often correlated with physical activity participation, this is not always the case. Therefore, it may be just as important to consider the activity an individual is not doing when evaluating health and well-being. This Editorial will summarize the importance of distinguishing between physical activity and sedentary behaviour. It will also discuss how wearable technology, in the form of fitness trackers, may be used to encourage someone to break up sedentary bouts more often. Finally, we will consider important future research directions.

Energy Availability Is Associated With Luteinizing Hormone Pulse Frequency and Induction of Luteal Phase Defects.

OBJECTIVE: Determine the interrelations between reductions in energy availability (EA), luteinizing hormone (LH) pulse frequency, and the induction of menstrual disturbances in previously sedentary, ovulatory women. METHODS: Secondary analysis of a randomized controlled trial consisting of a 3-month controlled diet and supervised exercise program. EA was calculated daily by measured energy intake (kcal) and exercise energy expenditure (kcal) normalized to fat-free mass (kg) and averaged during baseline and each of 3 intervention menstrual cycles. Blood samples were obtained every 10 minutes for 24 hours in the early follicular phase before the intervention and after 3 months of diet and exercise (n = 14). LH pulse dynamics were assessed by Cluster. Linear mixed models determined whether EA predicts LH pulse frequency and LH pulse frequency predicts luteal phase defects (LPDs). RESULTS: Subjects were 20 ± 1 years old, 165.1 ± 1.4 cm tall, and weighed 58.9 ± 1.5 kg. LH pulse frequency decreased from 0.82 ± 0.06 pulses/h to 0.63 ± 0.09 pulses/h (P = 0.048) as a result of the intervention which produced modest (-3.2 ± 0.6 kg) weight loss. EA, averaged across a menstrual cycle, predicted LH pulse frequency (P = 0.003) such that a single-unit decrease in EA was associated with a 0.017 pulses/h decrease in LH pulse frequency. LH pulse frequency in cycles with LPDs was 49% of that observed in cycles with no menstrual disturbances and for every 0.1-unit decrease in LH pulse frequency, the odds of having an LPD were 22× greater than having an optimal ovulatory cycle (P = 0.01). CONCLUSIONS: Modest reductions in EA over a prolonged period are associated with decreased LH pulse frequency and the induction of menstrual disturbances.

Discriminating hypothalamic oligomenorrhea/amenorrhea from hyperandrogenic oligomenorrhea/amenorrhea in exercising women.

The mechanism underlying oligo/amenorrhea in exercising women is often presumed as hypothalamic inhibition secondary to energy deficiency; however, hyperandrogenism may provide an alternative mechanism in some exercising women. Our purpose was to compare reproductive, metabolic, and androgen profiles of exercising women with eumenorrheic, ovulatory menstrual cycles (n = 91), oligo/amenorrhea without evidence of hyperandrogenism (Oligo/Amen; n = 83), and oligo/amenorrhea with evidence of hyperandrogenism (Oligo/Amen-HA; n = 17), and determine the prevalence of oligo/amenorrhea with evidence of hyperandrogenism in exercising women. Self-reported menstrual history and quantification of daily estrogen and progesterone urinary metabolites determined reproductive status. Resting energy expenditure, body composition, and metabolic hormone concentrations determined metabolic status. Serum androgens and calculated free androgen index (FAI) determined androgen status. Groups were similar in age (22.4 ± 0.3 years), height (165.1 ± 0.5 cm), resting energy expenditure (1198.4 ± 12.0 kcal/day), and total triiodothyronine (85.0 ± 1.5 ng/dL) concentration. Oligo/Amen-HA had greater weight (60.0 ± 1.6, 56.1 ± 0.7 kg), body mass index (22.3 ± 0.4, 20.6 ± 0.2 kg/m2), percentage body fat (27.3% ± 1.4%, 24.4% ± 0.6%), fat mass (16.2 ± 1.0, 13.8 ± 0.4 kg), insulin (5.8 ± 0.7, 4.2 ± 0.3 µIU/mL), leptin (12.2 ± 2.3, 6.6 ± 0.7 ng/mL), FAI (6.1 ± 0.3, 1.7 ± 0.1), and luteinizing hormone/follicle-stimulating hormone (1.9 ± 0.3, 1.3 ± 0.2) compared with Oligo/Amen, respectively. In our sample, 17% of those with oligo/amenorrhea had concurrent hyperandrogenism. This study supports that oligo/amenorrhea in some exercising women is related to hyperandrogenism. Novelty Caution must be utilized when discriminating hypothalamic oligo/amenorrhea from hyperandrogenic oligo/amenorrhea. In our sample, 17% of those with presumed hypothalamic oligo/amenorrhea had concurrent hyperandrogenism. Exercise and/or mild energy deficiency may be protective against developing severe hyperandrogenic symptoms.

Opportunities of Wearable Technology to Increase Physical Activity in Individuals with Chronic Disease: An Editorial.

In this editorial, we will discuss one promising tool to encourage physical activity participation in individuals with chronic disease: The use of wearable technology.

Drive for Thinness Predicts Musculoskeletal Injuries in Division II NCAA Female Athletes.

The female athlete triad is the interrelation of low energy availability, menstrual dysfunction, and low bone mineral density. Previously, the components of the female athlete triad have been linked to bone stress injuries. The objective of this study was to explore the relationship between drive for thinness, a proxy indicator of low energy availability, and musculoskeletal injuries. Fifty-seven female athletes, from an NCAA Division II college, were followed throughout their respective sport season for musculoskeletal injuries. Women were grouped based on a median split of the drive for thinness score (high drive for thinness (DT) vs. low DT). At the end of each sport season, injury data were compiled using an electronic medical record database. Forty-seven of the 57 women (82%) incurred 90 musculoskeletal injuries. The most prevalent injuries included: Low back pain/spasm/strain (n = 12), followed by shin splints/medial tibial stress syndrome (n = 9), general knee pain (n = 7), quadriceps strain (n = 6), and knee sprain (anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, and lateral collateral ligament sprains; n = 5). The number of in-season injuries in the High DT group (2.0 ± 0.3) was significantly higher than the Low DT group (1.2 ± 0.2, p = 0.026). A high drive for thinness is associated with an increased number of injuries during the competitive season.

Impaired vascular function in exercising anovulatory premenopausal women is associated with low bone mineral density.

In estrogen-deficient post-menopausal women, osteoporosis shares a common link with cardiovascular disease risk, including endothelial dysfunction. The current study sought to examine associations between bone mineral density (BMD) and endothelial function in estrogen-deficient premenopausal women with exercise-associated menstrual disturbances. Recreationally trained women (24.3 ± 0.8 years; overall mean ± SEM) who were estrogen deficient (amenorrheic or eumenorrheic anovulatory cycles; E2Def; n = 13) or estrogen replete (eumenorrheic ovulatory cycles; E2Rep; n = 14) were studied. Total body and lumbar BMD (L1-L4) were determined using dual-energy X-ray absorptiometry. Serum markers of oxidative stress (oxidized low-density lipoprotein; OxLDL), energy deficiency (triiodothyronine), and bone turnover (osteocalcin, c-telopeptide X, P1NP) were assessed. Estrogen exposure was determined by assessing daily urinary estrone-3-glucuronide (E1G) across a monitoring period. Calf blood flow (CBF), an index of endothelial function, was measured using strain-gauge plethysmography. CBF, total body and L1-L4 BMD, triiodothyronine and E1G were lower (P < 0.05), and c-telopeptide crosslinks higher (P < 0.05) in E2Def. Osteocalcin and OxLDL did not differ (P > 0.05) between groups. L1-L4 BMD, osteocalcin, and E1G were the strongest predictors of CBF (R2 =0.615, P < 0.001). CBF was the strongest predictor of L1-L4 BMD (R2 =0.478, P < 0.001). L1-L4 (r = 0.558, P = 0.008) and CBF (r = 0.534, P = 0.004) were independently correlated with E1G. In young recreationally trained premenopausal women with anovulatory menstrual disturbances, low CBF predicts decreased lumbar BMD, suggesting impaired peripheral endothelial function may predict early unfavorable changes in bone metabolism. This finding may be of relevance in the early detection of cardiovascular and bone health decrements in otherwise healthy estrogen-deficient premenopausal women.

Taste and food reinforcement in non-overweight youth.

Food reinforcement is related to increased energy intake, cross-sectionally related to obesity and prospectively related to weight gain in children, adolescents and adults. There is very limited research on how different characteristics of food are related to food reinforcement, and none on how foods from different taste categories (sweet, savory, salty) are related to food reinforcement. We tested differences in food reinforcement for favorite foods in these categories and used a reinforcing value questionnaire to assess how food reinforcement was related to energy intake in 198 non-overweight 8- to 12-year-old children. Results showed stronger food reinforcement for sweet foods in comparison to savory or salty foods. In multiple regression models, controlling for child sex, minority status and age, average reinforcing value was related to total energy and fat intake, and reinforcing value of savory foods was related to total energy and fat intake. Factor analysis showed one factor, the motivation to eat, rather than separate factors based on different taste categories. Liking ratings were unrelated to total energy intake. These results suggest that while there are differences in the reinforcing value of food by taste groups, there are no strong differences in the relationship between reinforcing value of food by taste groups and energy or macronutrient intake.

Energy availability discriminates clinical menstrual status in exercising women.

BACKGROUND: Conditions of low energy availability (EA) (<30 kcal/kgLBM) have been associated with suppressed metabolic hormones and reductions in LH pulsatility in previously sedentary women during short-term manipulations of energy intake (EI) and exercise energy expenditure (EEE) in a controlled laboratory setting. The purpose of this study was to examine if EA, defined as EA = (EI-EEE)/kgLBM, is associated with disruptions in ovarian function in exercising women. METHODS: Menstrual status was confirmed with daily measures of urinary reproductive metabolites across 1-3 menstrual cycles or 28-day monitoring periods. EA was calculated for exercise days using EI from 3-day diet logs, EEE from heart-rate monitors and/or exercise logs for a 7-day period, and body composition from DXA. Resting energy expenditure (REE) was measured by indirect calorimetry. Total triiodothyronine (TT3) was measured from a fasting blood sample. RESULTS: 91 exercising women (23.1 ± 0.5 years) were categorized clinically as either exercising amenorrheic (ExAmen, n = 30), exercising oligomenorrheic (ExOligo, n = 20) or exercising eumenorrheic (ExEumen, n = 41). The eumenorrheic group was further divided into more specific subclinical groups as either exercising ovulatory (ExOv, n = 20), exercising inconsistent (ExIncon, n = 13), or exercising anovulatory (ExAnov, n = 8). An EA threshold of 30 kcal/kgLBM did not distinguish subclinical menstrual status (χ (2) = 0.557, p = 0.46) nor did EA differ across subclinical disturbance groups (p > 0.05). EA was lower in the ExAmen vs. ExEumen (30.9 ± 2.4 vs. 36.9 ± 1.7 kcal/kgLBM, p = 0.04). The ratio of REE/predicted REE was lower in the ExAmen vs. ExEumen (0.85 ± 0.02 vs. 0.92 ± 0.01, p = 0.001) as was TT3 (79.6 ± 4.1 vs. 95.3 ± 2.9 ng/mL, p = 0.002). CONCLUSIONS: EA did not differ among subclinical forms of menstrual disturbances in a large sample of exercising women, but EA did discriminate clinical menstrual status, i.e., amenorrhea from eumenorrhea.

FTO polymorphisms moderate the association of food reinforcement with energy intake.

Food reinforcement (RRVfood) is related to increased energy intake, cross-sectionally related to obesity, and prospectively related to weight gain. The fat mass and obesity-associated (FTO) gene is related to elevated body mass index and increased energy intake. The primary purpose of the current study was to determine whether any of 68 FTO single nucleotide polymorphisms (SNPs) or a FTO risk score moderate the association between food reinforcement and energy or macronutrient intake. Energy and macronutrient intake was measured using a laboratory ad libitum snack food consumption task in 237 adults of varying BMI. Controlling for BMI, the relative reinforcing value of reading (RRVreading) and proportion of African ancestry, RRVfood predicted 14.2% of the variance in energy intake, as well as predicted carbohydrate, fat, protein and sugar intake. In individual analyses, six FTO SNPs (rs12921970, rs9936768, rs12446047, rs7199716, rs8049933 and rs11076022, spanning approximately 251kbp) moderated the relationship between RRVfood and energy intake to predict an additional 4.9-7.4% of variance in energy intake. We created an FTO risk score based on 5 FTO SNPs (rs9939609, rs8050136, rs3751812, rs1421085, and rs1121980) that are related to BMI in multiple studies. The FTO risk score did not increase variance accounted for beyond individual FTO SNPs. rs12921970 and rs12446047 served as moderators of the relationship between RRVfood and carbohydrate, fat, protein, and sugar intake. This study shows for the first time that the relationship between RRVfood and energy intake is moderated by FTO SNPs. Research is needed to understand how these processes interact to predict energy and macronutrient intake.

A case report of recovery of menstrual function following a nutritional intervention in two exercising women with amenorrhea of varying duration.

Increasing caloric intake is a promising treatment for exercise-associated amenorrhea, but strategies have not been fully explored. The purpose of this case report was to compare and contrast the responses of two exercising women with amenorrhea of varying duration to an intervention of increased energy intake. Two exercising women with amenorrhea of short (3 months) and long (11 months) duration were chosen to demonstrate the impact of increased caloric intake on recovery of menstrual function and bone health. Repeated measures of dietary intake, eating behavior, body weight, body composition, bone mineral density, resting energy expenditure, exercise volume, serum metabolic hormones and markers of bone turnover, and daily urinary metabolites were obtained. Participant 1 was 19 years old and had a body mass index (BMI) of 20.4 kg/m(2) at baseline. She increased caloric intake by 276 kcal/day (1,155 kJ/day, 13%), on average, during the intervention, and her body mass increased by 4.2 kg (8%). Participant 2 was 24 years old and had a BMI of 19.7 kg/m(2). She increased caloric intake by 1,881 kcal/day (7,870 kJ/day, 27%) and increased body mass by 2.8 kg (5%). Resting energy expenditure, triiodothyronine, and leptin increased; whereas, ghrelin decreased in both women. Resumption of menses occurred 23 and 74 days into the intervention for the women with short-term and long-term amenorrhea, respectively. The onset of ovulation and regular cycles corresponded with changes in body weight. Recovery of menses coincided closely with increases in caloric intake, weight gain, and improvements in the metabolic environment; however, the nature of restoration of menstrual function differed between the women with short-term versus long-term amenorrhea.

Decreased luteinizing hormone pulse frequency is associated with elevated 24-hour ghrelin after calorie restriction and exercise in premenopausal women.

Elevated ghrelin has been shown to be associated with reduced luteinizing hormone (LH) pulsatility in Rhesus monkeys, rats, men, and recently women. We previously reported that 24-h ghrelin concentrations are elevated in women following a 3-mo exercise and diet program leading to weight loss. We investigated whether the elevations in ghrelin following an ~3-mo exercise and diet program leading to weight loss are associated with a decrease in LH pulsatility. The nonexercising control group (Control, n = 5) consumed a controlled diet that matched energy needs, whereas energy intake in the exercise group (Energy Deficit, n = 16) was reduced from baseline energy requirements and supervised exercise training occurred five times per a week. Significant decreases in body weight (-3.0 ± 0.6 kg), body fat (-2.9 ± 0.4 kg) and 24-h LH pulse frequency (-0.18 ± 0.08 pulses/h), and a significant increase in 24-h mean ghrelin were observed in only the Energy Deficit group. The pre-post change in LH pulse frequency was negatively correlated with the change in mean 24-h ghrelin (R = -0.485, P = 0.030) and the change in peak ghrelin at lunch (R = -0.518, P = 0.019). Interestingly, pre-post change in night LH pulse frequency was negatively correlated with the change in mean day ghrelin (R = -0.704, P = 0.001). Elevated total ghrelin concentrations are associated with the suppression of LH pulsatility in premenopausal women and may play a role in the suppression of reproductive function following weight loss.

The association of a high drive for thinness with energy deficiency and severe menstrual disturbances: confirmation in a large population of exercising women.

A high drive-for-thinness (DT) score obtained from the Eating Disorder Inventory-2 is associated with surrogate markers of energy deficiency in exercising women. The purposes of this study were to confirm the association between DT and energy deficiency in a larger population of exercising women that was previously published and to compare the distribution of menstrual status in exercising women when categorized as high vs. normal DT. A high DT was defined as a score ≥7, corresponding to the 75th percentile for college-age women. Exercising women age 22.9 ± 4.3 yr with a BMI of 21.2 ± 2.2 kg/m2 were retrospectively grouped as high DT (n = 27) or normal DT (n = 90) to compare psychometric, energetic, and reproductive characteristics. Chi-square analyses were performed to compare the distribution of menstrual disturbances between groups. Measures of resting energy expenditure (REE) (4,949 ± 494 kJ/day vs. 5,406 ± 560 kJ/day, p < .001) and adjusted REE (123 ± 16 kJ/LBM vs. 130 ± 9 kJ/LBM, p = .027) were suppressed in exercising women with high DT vs. normal DT, respectively. Ratio of measured REE to predicted REE (pREE) in the high-DT group was 0.85 ± 0.10, meeting the authors' operational definition for an energy deficiency (REE:pREE <0.90). A greater prevalence of severe menstrual disturbances such as amenorrhea and oligomenorrhea was observed in the high-DT group (χ2 = 9.3, p = .003) than in the normal-DT group. The current study confirms the association between a high DT score and energy deficiency in exercising women and demonstrates a greater prevalence of severe menstrual disturbances in exercising women with high DT.

Ghrelin but not peptide YY is related to change in body weight and energy availability.

PURPOSE: The aim of this study was to examine changes in fasting total peptide YY (PYY) and ghrelin in nonobese premenopausal women after an exercise and diet program with and without weight loss. METHODS: Body composition, energy balance parameters, ghrelin, and PYY were measured before and after a 3-month intervention in nonexercising controls (n = 7) and exercising women who either remained weight stable (n = 5) or lost weight (n = 10). At baseline, subjects were 20.6 ± 2.2 yr, weighed 58.0 ± 4.8 kg, and had 27.2% ± 4.9% body fat. Supervised exercise training occurred five times a week for up to 90 min at 70%-80% of maximum HR. Subjects were fed a controlled diet. RESULTS: Body weight (-3.2 ± 0.8 kg) and fat mass (-2.6 ± 0.7 kg) decreased significantly in the weight-loss exercise group. Neither fasting ghrelin nor PYY changed in response to exercise training in the absence of weight loss, and PYY did not change with exercise and weight loss. Fasting ghrelin did reveal a significant time × experimental group interaction (P = 0.025). The change in ghrelin was inversely correlated with the change in body weight, body mass index, fat-free mass, and energy availability. CONCLUSIONS: Neither fasting ghrelin nor fasting PYY seem to play a role in the adaptive changes associated with exercise training when exercise occurs in the absence of weight loss. Fasting ghrelin concentrations increase when body weight is lost and may respond to even smaller changes in energy availability. However, fasting PYY does not seem to play a key role in the regulation of energy balance during diet- and exercise-associated weight loss.

Menstrual irregularities and energy deficiency in physically active women: the role of ghrelin, PYY and adipocytokines.

Menstrual cycle irregularities are often observed among physically active women and athletes who participate in physical activity ranging from recreational to competitive exercise training. Further, such irregularities have been casually linked to an energy deficiency where caloric intake is inadequate for exercise energy expenditure resulting in a suppressive effect on growth and reproduction. Adaptations consistent with chronic energy deficiency, including reductions in resting energy expenditure and total triiodothyronine, have been observed in exercising women with functional hypothalamic amenorrhea (FHA). Gut peptides and adipocytokines also appear to be altered in exercising women with FHA and have been hypothesized to be involved in the etiology of FHA. Ghrelin concentrations are elevated in exercising women with FHA. Interestingly, while fasting ghrelin, an orexigenic peptide, is elevated in women with FHA, PYY, an orexigenic peptide, is paradoxically also elevated in women with anorexia nervosa and exercising women with FHA. Leptin, an adipocytokine, is also suppressed in FHA associated with exercise and anorexia. A critical leptin concentration threshold is suggested to be necessary for regular menses to occur. Ghrelin, PYY, and leptin all have the ability to cross the blood brain barrier and, in the hypothalamus, can modulate appetite and food intake, and are hypothesized to affect the hypothalamic-pituitary-ovarian axis. Future studies are needed to determine if ghrelin, PYY, or leptin play a direct role in the regulation of the hypothalamic-pituitary-ovarian axis, and if these signals can be altered by improving energy status secondary to increasing caloric intake and initiate the reversal of amenorrhea.