Weight Control Behaviors Among Adult Men and Women: Cause for Concern?

NEUMARK-SZTAINER, DIANNE, NANCY E. SHERWOOD, SIMONE A. FRENCH, AND ROBERT W. JEFFERY. Weight control behaviors among adult men and women: cause for concern? Obes Res. Objectives To examine gender differences in weight control behaviors; their duration and the consistency of their use over a 3-year period; and variations of these behaviors by body mass index (BMI). Research Methods and Procedures The study population included 714 women and 229 men participating in a community-based weight gain prevention program who completed surveys about their weight control behaviors annually for 3 years. General dieting behaviors (e.g., current, regular, and past dieting), dietary restraint (using Restrained Eating subscale of the Three-Factor Eating Questionnaire), and specific weight control practices (e.g., increasing exercise, skipping meals, and taking laxatives) were assessed. Results Women were more likely than men to report weight control behaviors, with particularly strong associations found between gender and “history of dieting” (odds ratio = 8.1) and “participation in an organized weight loss program” (odds ratio = 11.7). Among both genders, exercise was the most frequently reported specific weight loss practice (66% of women and 53% of men), followed by decreasing fat intake (62% of women and 48% of men). The use of at least one unhealthy weight control behavior over the past year was reported by 22% of the women and 17% of the men. Gender differences were not found for duration of use of most of the specific weight control practices over the past year, or for consistency of general dieting behaviors and dietary restraint over time. Although both gender and BMI were strongly associated with dieting behaviors, interactions between gender and BMI on prevalence rates of dieting were not significant. Discussion Although weight control behaviors were more prevalent among women than men, in general, large gender differences were not found in the types of behaviors used and the duration and consistency of their use. The high percentages of adults using healthy methods of weight control was encouraging. However, there is still cause for concern, in that unhealthy weight control practices were also reported by a significant percentage of the population.     

Dieting Status and Its Relationship to Weight,Dietary Intake,and Physical Activity Changes Over Two Years in a Working Population

The present study prospectively examined changes in dietary intake, physical activity and weight associated with self-reported efforts to lose weight in a cohort of 3671 men and women sampled from the general population. Dieting efforts, dietary intake, physical activity and weight were measured at two points in time, 24 months apart. At baseline, current dieters reported consuming fewer dairy products, sweets, meat, soft drinks and fried potatoes (all p's < .0001), and engaging more frequently in high-intensity physical activity (p < .0001) than those not currently dieting. At follow-up, current dieters reported consuming fewer sweets (p < .0001) and fried potatoes (p < .0008), and engaging more frequently in moderate-intensity physical activity (p < .02) than those not currently dieting. Prospectively, those who initiated weight-loss diets showed the largest decrease in consumption of sweets (p < .0001), soft drinks (p < .0001), and fried potatoes (p < .01), and increase in frequency of high-intensity physical activity (p < .0001) and moderate-intensity physical activity (p < .007). Those initiating weight-loss diets were the only group to lose weight (1 lb.). Those dieting at baseline but not at follow-up gained the most weight (4 lbs.). Self-reports of current dieting correspond to reported changes in dietary intake and physical activity, and to measured changes in weight over the same time period. Individuals who report dieting to lose weight have healthier eating and exercise patterns than those who do not report dieting.     

Body Size Perceptions and Eating Attitudes in Elderly Men

The majority of studies on eating attitudes, dieting and body size perceptions have focused on young adults and women. This study examined these attitudes in 334 black and white men, ages 55 to 98 years, who were members of the Charleston Heart Study cohort. Associations of the eating attitude variable with race, education and weight status were examined. Eighty-two percent of the overweight white men studied had dieted to lose weight, whereas only 49% of slimmer white men had dieted. In contrast, overweight black men did not diet more than slimmer black men. Overall black men dieted less than white men (37% reported dieting). Black men who were high school graduates were 1.3 times more likely to have dieted than were less educated black men. Overweight white men were over twice as likely as slimmer white men to feel guilty after overeating. This difference was not found in overweight versus slimmer black men. Education was not associated with measured body mass index (BMI) or perceived or ideal body size. However, there were some racial differences in these variables. White men preferred to be slightly thinner than black men (ideal BMI 25.6 vs. 26.1 kg/m²), and the difference between actual and desired BMI was 0.6 kg/m² greater in white than in black men. These results indicate that effects of race and weight status on eating restraint and body size perceptions seen in younger subjects and in women are also present, at least to some degree, in elderly men.     

Diet and Physical Activity Behaviors among Americans Trying to Lose Weight: 2000 Behavioral Risk Factor Surveillance System

Objective: To examine the prevalence and correlates of trying to lose weight among U.S. adults, describe weight loss strategies, and assess attainment of recommendations for weight control (eating fewer calories and physical activity). Research Methods and Procedures: This study used the Behavioral Risk Factor Surveillance System, a state‐based telephone survey of adults ≥18 years of age (N = 184, 450) conducted in the 50 states, the District of Columbia, and Puerto Rico in 2000. Results: The prevalence of trying to lose weight was 46% (women) and 33% (men). Women reported trying to lose weight at a lower BMI than did men; 60% of overweight women were trying to lose weight, but men did not reach this level until they were obese. Adults who had a routine physician checkup in the previous year and reported medical advice to lose weight vs. checkup and no medical advice to lose weight had a higher prevalence of trying to lose weight (81% women and 77% men vs. 41% women and 28% men, respectively). The odds of trying to lose weight increased as years of education increased. Among respondents who were trying to lose weight, ～19% of women and 22% of men reported using fewer calories and ≥150 min/wk leisure‐time physical activity. Discussion: A higher percentage of women than men were trying to lose weight; both sexes used similar weight loss strategies. Education and medical advice to lose weight were strongly associated with trying to lose weight. Most persons trying to lose weight were not using minimum recommended weight loss strategies.     

Are general practitioners doing enough to promote healthy lifestyle? Findings of the Medical Research Council's general practice research framework study on lifestyle and health.

The health survey questionnaire was used to collect information about cigarette smoking, alcohol consumption, physical exercise, and dieting and weight. Completed questionnaires were received from 25,496 men and 36,657 women registered with 47 group practices in England and Scotland. The proportions of respondents who stated that they had a problem ranged from 1% (women and drinking, n = 406) to 34% (women and weight, n = 12,526). Between 49% (women and drinking, n = 18,048) and 67% (men (n = 17,095) and women (n = 24,550) and weight) thought that their general practitioners should be interested in their lifestyle. The proportions who could recall having received relevant advice ranged from 2% (women and drinking, n = 591) to 24% (women and weight, n = 8946). Advice about smoking had been given to 4055 (40%) of the women and 2941 (39%) of the men who smoked. Only 96 (10%) of the 989 women and 331 (17%) of the 1948 men who drank excessively could recall having received advice about alcohol consumption. These results suggest that patients are concerned about their lifestyle, that most would welcome relevant counselling, and that doctors should become more concerned with prevention of this kind.     

Prevalence of Overweight and Obesity and Weight Loss Practice among Beijing Adults, 2011

Objective

This study aims to determine the up-to-date prevalence of overweight and obesity, the distributions of body weight perception and weight loss practice in Beijing adults.

Methods

A cross-sectional study was conducted in 2011. A total of 2563 men and 4088 women aged 18–79 years from the general population were included. Data were obtained from questionnaire and physical examination.

Results

The prevalence of overweight (BMI 24–27.9 kg/m²) and obesity (BMI≥28 kg/m²) was 42.1% and 20.3% in men and 35.6% and 17.1% in women, respectively. Age was inversely associated with overweight in both sexes, and obesity in women. Education level was negatively associated with overweight and obesity in women but not in men. Only 49.1% men and 58.3% women had a correct perception of their body weight. Underestimation of body weight was more common than overestimation, especially in men, the older people, and those with low education level. The percentage of taking action to lose weight was inversely associated with men and old age, and positively associated with higher education level, higher BMI, and self-perception as “fat” (OR = 3.78 in men, OR = 2.91 in women). Only 26.1% of overweight/obese individuals took action to lose weight. The top two weight loss practices were to reduce the amount of food intake and exercise.

Conclusion

Overweight and obesity were highly prevalent with high incorrect body weight perceptions in the general adult population in Beijing. Weight loss practice was poor in overweight and obese individuals. Actions at multiple levels are needed to slow or control this overweight and obesity epidemic.     

Obesity and Weight Control Practices in 2000 Among Veterans Using VA Facilities

Objective: To examine obesity prevalence and weight control practices among veterans who use Department of Veterans Affairs (VA) medical facilities (VA users). Research Methods and Procedures: Data from the 2000 Behavioral Risk Factor Surveillance System, a telephone survey of 184, 450 adults, were analyzed. Outcome measures included BMI, weight control practices (the intent to manage weight, and diet and physical activity patterns), and receipt of professional weight control advice. Results: Of VA users, 44% were overweight and 25% were obese. After controlling for demographic factors, VA users were somewhat less likely to be overweight (odds ratio, 0.86; 95% confidence interval, 0.74 to 1.00) but equally likely to be obese (odds ratio, 1.08; 95% confidence interval, 0.92 to 1.27), compared with non‐VA users. Among obese VA users, 75% reported trying to lose weight, and another 17% reported trying to maintain weight. Of these, only 40% decreased both calorie and fat intake. Only 27% of obese VA users who reported increasing exercise to lose weight followed recommendations for regular and sustained physical activity. Of obese VA users, 59% were inactive or irregularly active. Only 51% of obese VA users received professional advice to lose weight. Obese VA users were more likely than obese non‐VA users to report trying to lose weight, modifying diet to lose weight by decreasing both calories and fat intake, and receiving professional weight control advice. Discussion: Interventions for weight management programs in VA facilities need to take into account the high prevalence of overweight/obesity among VA users and should emphasize effective weight control practices.     

Weight Loss and Gender: An Examination of Physician Attitudes

Objective: The purpose of this study was to investigate physician attitudes toward the treatment of overweight and obese individuals and to evaluate potential gender differences in treatment recommendations. Research Methods and Procedures: A survey describing several hypothetical patients was sent to 700 randomly selected physicians; 209 (29.9%) returned the survey. Two versions of the questionnaire (one for men and one for women) described three hypothetical patients at three levels of body mass index (BMI) (32, 28, and 25 kg/m²). One‐half of the physicians received a version of the questionnaire describing the patients as women, and one‐half received a version describing the patients as men. Respondents answered questions about attitudes toward treatment and specific interventions and referrals they would view as appropriate. Results: Physicians were more likely to encourage women with a BMI of 25 kg/m² to lose weight than men with the same BMI, and indicated that they would suggest more treatment referrals for women than men. Men with a BMI of 32 kg/m² were more likely to be encouraged to lose weight than women with the identical BMI. Physicians were more likely to encourage weight loss and see treatment referrals as appropriate for patients with higher BMIs. Discussion: This study indicates that physicians treat male and female patients differently, with physicians more likely to encourage weight loss and provide referrals for women with a BMI of 25 kg/m² than for men with an identical BMI and less likely to encourage weight loss for women than men with a BMI of 32 kg/m².     

Correlations with Self-Reported Weight Loss in Overweight U.S. Adults

The authors investigated two issues among overweight men and women in the U.S.: 1) what is the influence of the self-expressed intention to lose weight in the presence of other potential predictors of loss and 2) what are easily identifiable predictors of intentional weight loss during a 1-year recall period. The sample consisted of 1996 overweight men (body mass index (BMI ≥ 27.8 kg/m²) and 2586 overweight women (BMI ≥ 27.3 kg/m²) who answered questions regarding 1-year weight change in a Current Health Topic supplement of the population-based 1989 National Health Interview Survey. Of these overweight persons, 56.8% of men and 72.1% of women attempted to lose weight during the previous year. The most important characteristic associated with weight loss was the expressed intention itself. For any weight loss, the odds ratios (95% confidence intervals) for intention were 4.6 (3.6?5.9) for men and 3.8 (2.8?5.0) for women. Controlling for other factors reduced the odds only slightly, to 4.3 for men and 3.5 for women. Among women, older age, having a greater frequency of blood pressure checks, and being in poorer health reduced the influence of intent as a predictor of loss. To address the second objective, the identification of predictors of intentional 1-year weight loss, analysis was restricted to overweight persons who attempted to lose weight. For both sexes, statistically significant predictors (p<0.05) included never being married, smoking, higher BMI, being diabetic, and having a higher number of blood pressure checks. Being divorced or separated was predictive of weight loss in men only. Also, men were more likely to achieve weight loss than women. In conclusion, 1-year weight loss among the overweight was primarily a function of the intention to lose weight, although other factors contributed to determine whether weight loss was achieved.     

Racial/Ethnic and Gender Differences in Concern with Weight and in Bulimic Behaviors Among Adolescents

FIELD, ALISON E, GRAHAM A COLDITZ, KAREN E PETERSON. Racial/ethnic and gender differences in concern with weight and in bulimic behaviors among adolescents. This study examined cross-sectional gender and racial/ethnic differences in bulimic behaviors among adolescents. Subjects were 704 male and 621 female students at a large urban public high school in the Northeast. Approximately 61% of the girls and 43% of the boys reported trying to lose weight or maintain their current weight; 2.0% of the students reported using laxatives or vomiting to control their weight. The use of these behaviors to control weight was only slightly more common among girls than boys (2.7% vs. 1.4%,p=0.1). Although more black than white girls used laxatives or vomiting to control weight (odds ratio [OR]=11.9, 95% confidence interval [CI] 1.5–95.3), there were no racial/ethnic differences in these behaviors among boys. However, Hispanic boys were twice as likely as white boys to binge eat at least monthly (OR=2.0, 95% CI 1.1–3.6). Our results suggest that bulimic behaviors affect male and female adolescents from a variety of racial/ethnic backgrounds. In addition, in contrast to the large gender differences in the prevalence of dieting and binge eating, more modest differences were documented in the prevalence of using vomiting and laxatives to control weight.     

Dieting Frequency in Obese Patients With Binge Eating Disorder: Behavioral and Metabolic Correlates

This study examined the clinical significance of self‐reported frequency of time spent dieting in obese patients with binge eating disorder (BED). A total of 207 treatment‐seeking obese BED patients (57 men and 150 women) were dichotomized by dieting frequency and gender and compared on a number of historical, psychological, and metabolic variables. Frequent dieters reported significantly earlier age of onset for binge eating, dieting, and obesity, more episodes of weight cycling, greater weight suppression, and greater eating disorder pathology than infrequent dieters; no differences, however, emerged on current binge eating frequency or psychological distress. Among women but not among men, frequent dieters had consistently lower chances of abnormalities in total cholesterol, high‐density lipoprotein (HDL) cholesterol, and the total/HDL cholesterol ratio while infrequent dieters had greater chances of abnormalities on these variables. Dietary restraint was inversely correlated with abnormalities in triglycerides, HDL cholesterol, and the total/HDL cholesterol ratio but was unrelated to low‐density lipoprotein (LDL) cholesterol. In summary, frequent dieters of both genders had greater lifetime and current eating and weight concerns, and in women, decreased chance of metabolic abnormalities than infrequent dieters. Our findings suggest that frequent dieting attempts, particularly in women, are associated with greater eating disorder pathology but may have a beneficial effect on metabolic functioning and cardiovascular disease risk independent of actual weight status. These findings may have implications for clinical advice provided to obese BED patients.     

Self-Reported Substantial 1-Year Weight Change Among Men and Women in the United States

Population-based data have not been readily available on relatively short-term changes in weight. Therefore, we sought to determine the nature of self-reported substantial (> 10%) weight change over one year in a representative sample of the US population which participated in the 1989 National Health Interview Survey (NHIS). Across all ages, a larger proportion of women than men reported both weight loss as well as weight gain of any amount (18.9% vs. 16.1% for weight loss and 20.0% vs. 16.1% for weight gain). In sex-specific logistic regression analyses, significant risk factors common to both sexes for substantial weight loss included divorced/separated marital status, smoking, increased number of blood pressure checks, increased BMI (body mass index) and increased number of bed days. Black race reduced the risk of weight loss for both men and women. Sex-specific risk factors for weight loss in men only were widowhood or never married marital status, while increasing age was a protective factor in women only. Concerning weight gain > 10% over the past year, increased number of blood pressure checks and having one or more diabetic parents were significant risk factors among both men and women; while never being married, increased age, BMI, and education exerted a protective effect in both sexes. For women only, risk factors for weight gain included black race, increased number of contacts with a health professional, and being unemployed. Intention to lose weight was associated with both weight gain and weight loss in both sexes, although it did not serve as a confounder in any of these relationships. A greater likelihood of substantial weight loss among women relative to men was diminished for persons with higher BMI, higher number of blood pressure checks, being widowed, divorced or separated, and intention to lose weight. A greater likelihood of substantial weight gain among women relative to men was diminished for persons with low BMI. The results of this cross-sectional study of weight change, involving a one-year follow-up period, generally correspond with the results obtained by longitudinal studies involving a longer follow-up.     

Changes in obesity-related attitudes in women seeking weight reduction

Objective: To examine changes in obesity‐related attitudes in a sample of obese women who participated in either dieting or non‐dieting interventions. Research Methods and Procedures: A total of 123 obese women were randomly assigned to one of three weight control programs: meal replacement diet, balanced deficit diet, or a non‐dieting program. (The first two groups were combined as a single dieting condition.) Participants completed questionnaires (at baseline, Week 20, and Week 40) to assess beliefs and attitudes about obesity, along with measures of self‐esteem, depression, and body image. Results: At Weeks 20 and 40, participants in the non‐dieting condition reported significantly less negativity about obesity than those in the dieting group. Women in the dieting condition did not report an increase in negative attitudes toward obesity, despite losing significantly more weight than non‐dieting participants. Both groups experienced improvements in self‐esteem, body image, and depressive symptoms. Improvement in self‐esteem was associated with a reduction in negativity about obesity and with improvements in body image. Discussion: The non‐dieting program produced greater reductions in negative attitudes toward obesity than the dieting intervention. Dieting (with successful weight loss), however, did not result in greater negativity toward obesity. Non‐dieting programs seem to be useful in obese women for improving self‐esteem, body image, and internalized negative attitudes about obesity.     

Weight gain prevention among women

Objective: Women 25 to 45 years old are at risk for weight gain and future obesity. This trial was designed to evaluate the efficacy of two interventions relative to a control group in preventing weight gain among normal or overweight women and to identify demographic, behavioral, and psychosocial factors related to weight gain prevention. Research Methods and Procedures: Healthy women (N = 284), ages 25 to 44, with BMI < 30 were randomized to one of three intervention conditions: a clinic‐based group, a correspondence course, or an information‐only control. Intervention was provided over 2 years, with a follow‐up at Year 3. BMI and factors related to eating and weight were assessed yearly. Results: Over the 3‐year study period, 40% (n = 114) of the women remained at or below baseline body weight (±2 lbs), and 60% gained weight (>2 lbs). Intervention had no effect on weight over time. Independently of intervention, women who were older, not actively dieting to lose weight, and who reported less perceived hunger at baseline were more likely to be successful at weight maintenance. Weight maintenance also was associated with increasing dietary restraint (conscious thoughts and purposeful behaviors to control calorie intake) and decreasing dietary disinhibition (the tendency to lose control over eating) over time. Discussion: This study raises concern about the feasibility and efficacy of weight gain prevention interventions because most women were interested in weight loss, rather than weight gain prevention, and the interventions had no effect on weight stability. Novel approaches to the prevention of weight gain are needed.     

High school students' body weight control: differences between athletes and non-athletes

Due to chronic dissatisfaction with body weight in youth, efforts to lose weight often lead to pathological dietary behaviours. Regular and heavy sports activity may contribute to the optimization of body weight, not only by elevating the energy utilization but also by increasing the health consciousness and the tendency to self-monitor. Research generally finds a beneficial role of extracurricular sports activity in body weight control. Therefore, we aim to analyze how regular, heavy sports activity (more precisely, competitive sports) may contribute to body weight control among two groups of youth: athletes and non-athletes. Our study was carried out using 347 adolescents; among them there were 91 athletes and 259 controls. The subjects completed self-administered questionnaires concerning their body weight control and dietary habits. We found that girls were less satisfied with their body weight and reported dieting more frequently with a greater emphasis on healthy dieting than boys. Sport influenced these strong gender differences only regarding healthy dieting, young male athletes laid a larger emphasis on healthy diets than their non-athlete counterparts, therefore their attitude became similar to that of female athletes and non-athletes. We conclude that despite the normal weight in high school students, episodes of dieting that might contribute to eating disorders were quite frequent. This was not influenced by the students' extracurricular sports activity. A greater monitoring of male athletes' and their friend's diet draw attention to the need for developing health education programs specific to boys.     

Race and gender differences in the association of dieting and gains in BMI among young adults

Objective: To assess the relationship between dieting and subsequent weight change and whether the association varies by gender or race/ethnicity. Research Methods and Procedures: Male (n = 4100) and female (n = 4302) participants in the National Longitudinal Study of Adolescent Health who provided information on weight and height at baseline and two follow‐up assessments and were not missing information on weight control strategies or race were studied. Generalized estimating equations were used to assess whether dieting to lose or maintain weight at Wave I or II predicted BMI (kg/m²) change between adolescence and young adulthood (Wave II to III). Analyses were stratified by gender and took sampling weights and clustering into account. Results: At Wave I, the mean age of the participants was 14.9 years. Approximately 29.3% of female participants and 9.8% of male participants reported dieting in Wave I or II. Fewer African Americans than whites (6.2% vs. 10.0% and 25.5% vs. 31.2%, p = 0.007 and p = 0.02, among males and females, respectively) reported dieting. Between Waves II and III, participants gained on average 3.3 kg/m². Independent of BMI gain during adolescence (Waves I to II), female participants who dieted to lose or maintain weight during adolescence made larger gains in BMI during the 5 years between Waves II and III (mean additional gain, 0.39 kg/m²; 95% confidence interval, 0.08 to 0.71) than their nondieting peers. The association was not significant among the male participants. The association was largest among African‐American female participants. Discussion: The results suggest that not only is dieting to lose weight ineffective, it is actually associated with greater weight gain, particularly among female adolescents. Female African‐American dieters made the largest BMI gains.     

Weight-Related Attitudes and Behaviors of Women Who Diet to Lose Weight: A Comparison of Black Dieters and White Dieters

Obesity is a significant health problem among black women in the United States. Black women are two to three times more likely than white women to be obese. The present study sought to examine race differences in attitudes and beliefs about dieting, motivations underlying dieting efforts, and actual dieting strategies and behaviors. To achieve this aim, a subset of female survey respondents (n = 324) was drawn from a pool of more than 20,000 subscribers to Consumer Reports. All survey respondents had made at least one dieting effort within 3 years of the time of the study. For this study, we used all black female respondents (n = 162) and a matched sample (i.e., matched on age, educational attainment, and personal income) of white women (n = 162). Black women did weigh significantly more than Caucasian women, therefore, BMI was used as a covariate in all subsequent analyses. Black and white women were significantly different in a number of domains. Compared to white women, black women experienced less social pressure about their weight, initiated dieting later in life, and were significantly less likely to diet at each developmental milestone. However, the two groups of women did not differ in reasons for undertaking their most recent dieting efforts, or in the types of weight loss strategies they had employed. Nor were there differences between the black and white women in methods for coping responses with dietary relapse or in rates of disordered eating. These findings are discussed in terms of their implications for both treatment and prevention of obesity in black women.     

Exercise training enhances leg vasodilatory capacity of 65-yr-old men and women

To determine whether extremity vasodilatory capacity may be augmented in older persons by endurance exercise training, lower leg blood flow and conductance were characterized plethysmographically at rest and during maximal hyperemia in 9 men and 10 women aged 64 +/- 3 (SD) yr before and after 31 +/- 6 wk of walking and jogging at 70-90% of maximal oxygen uptake for 45 min 3-5 days/wk. Maximal oxygen uptake expressed as milliliters per kilogram per minute improved 25% in men and 21% in women (P less than 0.01). Maximal leg blood flow and conductance increased in all nine men by an average of 39 +/- 33 (P less than 0.001) and 42 +/- 44% (P less than 0.004), respectively. Results were more variable in women and achieved unequivocal statistical significance only for maximal blood flow (+33 +/- 54% for blood flow and +29 +/- 55% for conductance; P less than 0.02 and P = 0.05, respectively). Body weight and skinfold adiposity declined in both sexes (P less than 0.05). Enhancement of vasodilatory capacity was related to weight loss in men and adipose tissue loss in women (r = 0.61 and 0.51, respectively; P less than 0.05). There were no significant changes in exercise capacity, body weight, or maximal blood flow in four male and three female controls aged 66 +/- 4 yr. Thus adaptability of the lower limb circulation to endurance exercise training is retained to at least age 65 yr.     

Dissociated time course of recovery between genders after resistance exercise

Comparisons between men and women of time course responses of strength, delayed-onset muscle soreness (DOMS), and muscle swelling after a resistance training session are still controversial. Therefore, this study examined gender differences in strength loss, muscle thickness (MT), and DOMS between young men and women. Thirty apparently healthy, untrained volunteers (14 women and 16 men) participated in the study protocol. The resistance exercise session consisted of 8 sets at 10 repetition maximum load of the elbow flexor muscles of their dominant arm. Maximum isokinetic peak torque (PT), MT, and DOMS were recorded at baseline (TB), immediately after exercise (T0), and at 1 (T1), 2 (T2), 3 (T3), and 4 (T4) days after exercise. Baseline strength was expressed as 100%. There were no significant differences between the sexes for relative PT loss immediately after exercise (T0 = 74.31 ± 8.26% for men and 76.00 ± 6.31% for women). Also, PT was still significantly less than baseline from T1 to T4 for both genders. In contrast, recovery from PT was longer in women when compared with that in men. Muscle thickness responded similarly to PT in both genders. However, there was no significant difference between genders for DOMS at any time point. The time point that showed the greatest degree of mean soreness was T2 (4.94 ± 2.38 mm for men and 4.45 ± 2.07 mm for women). Our data suggest that after resistance exercise, women and men experience similar immediate strength loss; however they have dissimilar strength recovery across 4 days of recovery. Likewise, both genders experience a different time course of MT response after a traditional resistance exercise protocol. In contrast, men and women develop and dissipate muscle soreness in a similar manner.     

Sex differences in hormone-sensitive lipase expression, activity, and phosphorylation in skeletal muscle at rest and during exercise

Women have been shown to use more intramuscular triacylglycerol (IMTG) during exercise than men. To investigate whether this could be due to sex-specific regulation of hormone-sensitive lipase (HSL) and to use sex comparison as a model to gain further insight into HSL regulation, nine women and eight men performed bicycle exercise (90 min, 60% Vo(2peak)), and skeletal muscle HSL expression, phosphorylation, and activity were determined. Supporting previous findings, basal IMTG content (P < 0.001) and net IMTG decrease during exercise (P < 0.01) were higher in women than in men and correlated significantly (r = 0.72, P = 0.001). Muscle HSL mRNA (80%, P = 0.11) and protein content (50%, P < 0.05) were higher in women than in men. HSL total activity increased during exercise (47%, P < 0.05) but did not differ between sexes. Accordingly, HSL specific activity (HSL activity per HSL protein content) increased during exercise (62%, P < 0.05) and was generally higher in men than in women (82%, P < 0.05). A similar pattern was observed for HSL Ser(659) phosphorylation, suggesting a role in regulation of HSL activity. Likewise, plasma epinephrine increased during exercise (P < 0.05) and was higher in men than in women during the end of the exercise bout (P < 0.05). We conclude that, although HSL expression and Ser(659) phosphorylation in skeletal muscle during exercise is sex specific, total muscle HSL activity measured in vitro was similar between sexes. The higher basal IMTG content in women compared with men is therefore the best candidate to explain the higher IMTG net hydrolysis during exercise in women.