Higher Habitual Physical Activity Research Articles

Association of habitual physical activity with depression and anxiety: a multicentre cross-sectional study

ObjectiveDespite the known benefits of physical activity, the effect of habitual physical activity (HPA) on depression and anxiety remains unclear. This study aimed to investigate the association of HPA with...

How lifestyle shapes the brain: Associations between physical activity, sleep, beta‐amyloid and cognitive function in older adults

AbstractBackgroundLifestyle factors such as sleep and physical activity influence risk of cognitive decline and dementia. Higher habitual physical activity and optimal sleep are associated with better cognitive function and lower levels of Alzheimer’s disease biomarkers, including beta‐amyloid (Aß). There is currently a poor understanding of how physical activity may influence the relationship between sleep and cognition, and whether exercise and sleep interact to influence cognition and Aß. Developing this understanding is crucial for creating effective lifestyle interventions for dementia prevention.MethodData from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study were utilised to determine whether self‐reported physical activity moderates the cross‐sectional relationship between self‐reported sleep parameters (duration, efficiency, latency, disturbance, quality), cognitive function (episodic memory, attention and processing speed, executive function), and brain Aß (quantified by amyloid positron emission tomography, using the Centiloid scale). Analyses were adjusted for age, sex, APOE ε4 carriage, mood, premorbid intelligence, and collection point. Participants were 404 community‐dwelling cognitively normal older adults aged 60 and above (75.3 5.7 years). Data from a subset of participants (n = 220, aged 75.2 5.6 years) were used for analyses with AB as the outcome.ResultPhysical activity moderated the relationship between sleep duration and episodic memory (ß = ‐.09, SE = .03, p = .005), and sleep efficiency and episodic memory (ß = ‐.08, SE = .03, p = .016). Physical activity moderated the relationship between sleep duration and A® (ß = ‐.12, SE = .06, p = .036), and sleep quality and Aß (ß = .12, SE = .06, p = .029).ConclusionPhysical activity may play an important role in the relationship between sleep and cognitive function, and sleep and brain Aß. Future longitudinal and intervention studies in this area are crucial for informing interventions for dementia prevention.

Combined Effects of Chronic PM2.5 Exposure and Habitual Physical Activity on Cancer Mortality: A Longitudinal Cohort Study

BACKGROUND AND AIM: Physical activity (PA) may increase the inhalation and deposition of air pollutants, possibly reducing its beneficial effects. We thus examined the combined effects of chronic exposure to fine particle matter (PM2.5) and habitual PA on the risk of cancer mortality in Taiwan. METHODS: A total of 384,128 adults (≥18 years) with 842,384 medical examinations were recruited between 2001 and 2016. All participants were followed up until May 31, 2019. Vital data were obtained from the National Death Registry of Taiwan. Ambient PM2.5 exposure was estimated using a satellite-based spatiotemporal model. Information on habitual PA was collected using a standard self-administered questionnaire. The time-dependent Cox regression model was used to evaluate the combined effects. RESULTS:Higher habitual PA was associated with lower risk of cancer mortality, whereas higher PM2.5 exposure was associated with higher risk of cancer mortality. The inverse associations of habitual PA with cancer mortality were not modified by chronic exposure to PM2.5. Compared to the participants with inactive-low-PA and high-PM2.5, those with high-PA and low-PM2.5 exhibited a 35% lower risk of cancer mortality [95% confidence interval (CI): 28%-42%]. CONCLUSIONS:Increased PA and reduced PM2.5 exposure are associated with lower risk of cancer mortality. Habitual PA reduces the risk of cancer mortality regardless of the levels of chronic PM2.5 exposure. Our results indicate that habitual PA is a suitable health promotion strategy even for people residing in relatively polluted regions. KEYWORDS: Particulate matter, Long-term exposure, cancer mortality

Accelerometer-Assessed Habitual Physical Activity and Sedentary Time of Chinese Children and Adolescents with Visual Impairments

Introduction: Physical activity is a key component of a healthy lifestyle for youths with visual impairments (i.e., blindness or low vision). This study aims to examine the habitual physical activity and sedentary time of Chinese children and adolescents with visual impairments and to determine whether age, gender, and body composition significantly influence their behavior. Methods: A purposeful sample method was utilized to recruit 137 Chinese youths with visual impairments from a special school for individuals with visual and hearing impairments. A total of 72 students with visual impairments (aged 7–17 years; M age = 13.4) participated in this study. ActiGraph GT3X accelerometers were used to measure the habitual physical activity and sedentary time. Results: Youths with visual impairments in this study spent an average of 287.86 (standard deviation [ SD] = 45.67) minutes of light physical activity, 146.79 ( SD = 56.95) minutes of moderate physical activity, 18.47 ( SD = 15.15) minutes of vigorous physical activity, 165.26 ( SD = 69.83) minutes of moderate-to-vigorous-intensity physical activity, and 979.51 ( SD = 109.10) minutes of sedentary time per day. Children with visual impairments in elementary school engaged in more habitual physical activity and had less sedentary time than did students in middle and high school. Differences in gender and body composition with regard to time spent being active or sedentary were insignificant. Discussion: Findings demonstrated that Chinese youths with visual impairments in this study had sufficient health-enhancing physical activity and were habitually active. Future research is needed to identify the factors that account for the high habitual physical activity levels of Chinese youths with visual impairments. Implications for practitioners: Transition planning for students with visual impairments to facilitate active habitual physical activity participation when children grow up is warranted.

ASSOCIATION OF HABITUAL PHYSICAL ACTIVITY WITH HOME BLOOD PRESSURE: INSIGHTS FROM THE ELECTRONIC FRAMINGHAM HEART STUDY

A sedentary lifestyle is associated with increased risk for hypertension. Smartwatches enable accurate measurement of habitual physical activity. We hypothesize that higher habitual physical activity is associated with lower home blood pressure (BP). Electronic Framingham Heart Study (eFHS)

TYPOLOGICAL VARIABILITY OF PSYCHOPHYSIOLOGICAL FEATURES IN SCHOOLCHILDREN FOR PROGNOSING SUCCESS IN SPORTS AND HEALTH ENHANCEMENT ACTIVITIES

Aim. The purpose of the article is to provide a clinical and physiological assessment of adaptive variability of the psychophysiological status in schoolchildren and to obtain prognostic markers for forming success during health enhancement and sports activities. Materials and methods. 187 male schoolchildren of the first and second health group from secondary educational institutions in Tyumen participated in the study. A set of clinical and physiological methods was used. Habitual physical activity (HPA) was measured on a daily basis using Huawei Band 2 Pro (China) fitness tracker provided with accelerometer and gyroscope. The band is available for both Android (version 4.4 or later) and iOS 8.0 or later, which allows registering data at any time period. The type of partial body constitution was established according to a three-component scheme and a HPA level (low HPA – FTC-1, medium HPA – FTC-2, high HPA – FTC-3). Results. Based on the concept of typological variability of physiological individuality, a systemic relationship between the indicators of anxiety, aggressiveness and depression was established in primary schoolchildren with different levels of habitual physical activity (low – LHPA, medium – MHPA, high – HHPA) and of different functional types (FTC-1, FTC-2, FTC-3). Compared with other groups, primary schoolchildren with LHPA – FTC-1 showed an increase in general anxiety and a total indicator of depression, a decrease in mood, a negative assessment of their own inefficiency, and the lowest indicator of aggressiveness with an auto-aggressive orientation. In children with HHPA, there was a decrease in the general level of depression and mood, a negative assessment of generally accepted rules, aggressive behavior, a negative assessment of their own inefficiency combined with an increased level of aggressiveness of a heteroaggressive orientation. Conclusion. Clinical and physiological characteristics of three physiological norm variants (functional constitutional types, children with low (FTC-1), medium (FTC-2) and high (FTC-3) habitual physical activity) determined the selection of psychophysiological markers of stress reactivity in primary schoolchildren, which provides an objective basis for prognostic assessment and targeted success formation in sports and health enhancement activities, as well as the creation of effective monitoring of transition states and preventive forms for correcting dysregulation.

Habitual physical activity, renal function and chronic kidney disease: a cohort study of nearly 200 000 adults

BackgroundThere is limited information on the association between habitual physical activity (PA) and renal function.ObjectiveTo report the longitudinal association between self-reported habitual PA and measures of renal function in a...

Anthropometric Obesity Indices, Body Fat Percentage, and Grip Strength in Young Adults with different Physical Activity Levels.

The purposes of this study were to determine whether moderately physically active (MPA) and highly physically active (HPA) male (n = 96, age = 22.5 ± 1.7 years) and female (n = 85, age = 21.3 ± 1.6 years) young adults differed in their anthropometric obesity indices (AOIs), body fat percentage (BF%), and muscular strength, and also to examine the associations between physical activity level (PAL) and the abovementioned variables. Participants were measured for body height and weight, BF%, waist and hip circumferences, and maximal isometric grip strength. According to their PAL, estimated by the short version of the International Physical Activity Questionnaire, they were assigned to MPA and HPA subgroups. Regardless of gender, results indicated that participants in the MPA groups had significantly higher values of body weight, waist and hip circumference, BF%, and BMI than participants in the HPA groups. No significant differences were found between physical activity groups in terms of grip strength. The AOIs and BF% were found to be significantly and negatively correlated with the PAL in both genders. In conclusion, the findings of the study suggest that high habitual physical activity is associated with lower adiposity markers. However, the differences in the hand grip strength of the contrasting activity groups were negligible.

Physical Activity Modulates Blood Pressure Regulation During Controlled Low and High Salt Diets

PURPOSE: Increased blood pressure (BP) reactivity and variability are predictive of future cardiovascular events. Excess dietary salt exaggerates neurally-mediated BP reactivity, and BP variability in salt-resistant rodents. Regular physical activity (PA) blunts BP reactivity in rodents. However, the interaction of salt and PA on neurovascular regulation has not been investigated in humans. Therefore, we sought to test the hypothesis that high habitual PA mitigates high dietary salt-induced increases in BP reactivity and BP variability in healthy, young adults. METHODS: Nine participants (5F/4M, 27±2 yrs, BMI: 23.3±0.9 kg/m2) completed randomized, controlled 10-day diets of low (2.6 g/day), and high (18 g/day) salt. Beat-to-beat laboratory BP was measured via photoplethysmography on day 10 of each diet. BP reactivity was assessed as ΔBP (mmHg) during the final minute of a 2-min hand grip exercise at 40% maximal voluntary contraction compared to a preceding baseline. Average real variability (ARV) index was used to assess BP variability derived from 24-hour ambulatory BP monitoring. Habitual PA was assessed via accelerometry (Actigraph GT3X). Differences in high vs. low salt BP reactivity (ΔBP reactivity) and ambulatory BP variability (ΔBP ARV) were correlated against PA. Twenty four-hour urinary sodium excretion was measured. RESULTS: There were no differences in 24-hr mean arterial BP on the high vs. low salt diet (82.9±2.1 vs. 79.8±2.4 mmHg; p > 0.10). Urinary Na+ excretion increased on the high vs. low salt diet (256.9±20.5 vs. 39.5±11.2 mmol/24 hours; p < 0.05). There was a trend for the high salt diet to augment systolic (p = 0.08), but not diastolic BP reactivity during hand grip exercise. Habitual PA was inversely correlated to Δ systolic BP reactivity (r = -0.74, p = 0.03), and there was a trend for an inverse correlation with Δ diastolic BP reactivity (r = -0.68, p = 0.06) during hand grip exercise. There was a trend for higher 24-hr systolic BP ARV on the high salt diet (10.6±0.8 vs. 8.9±0.6 mmHg; p = 0.09), but there was no correlation between PA with Δ systolic BP ARV (r = -0.29, p = 0.48) on the high vs. low salt diet. CONCLUSION: These preliminary data suggest that high habitual physical activity may offset some of the adverse neurovascular effects of high dietary salt in young, healthy, salt-resistant humans.

High Habitual Physical Activity Improves Acute Energy Compensation in Nonobese Adults.

Evidence suggests that homeostatic satiety signaling is enhanced with higher levels of physical activity (PA), with active individuals demonstrating an improved ability to compensate for previous energy intake (EI). However, prior studies lacked objective assessment of both PA level and EI. This study examined the effect of objectively measured PA level on homeostatic (energy compensation) and hedonic (liking and wanting) responses to high-energy (HEP), low-energy (LEP), and control preloads. Thirty-four nonobese individuals were grouped by tertiles of accelerometry-measured habitual moderate-to-vigorous PA (low, LoMVPA; moderate, ModMVPA; high, HiMVPA), similar in age, sex, and body mass index. After a preliminary assessment, EI (fixed-energy breakfast and ad libitum lunch, dinner, and evening snack box meals) was determined for three probe meal days in which preloads varying in energy content (HEP, 699 kcal; LEP, 258 kcal; control, 0 kcal) were consumed before the lunch meal. Liking and wanting were assessed before and after preload consumption (Leeds Food Preference Questionnaire), and appetite ratings were taken throughout the day. Relative to control, EI at lunch was reduced to a greater extent after consumption of HEP compared with LEP in ModMVPA (P < 0.01) and HiMVPA (P = 0.01) but not LoMVPA (P = 0.59), reflecting more accurate energy compensation in HiMVPA and ModMVPA. There were no effects on cumulative EI after preload consumption of (lunch, dinner, and snack box combined). HEP led to a greater suppression of hunger, liking, and wanting compared with LEP in all MVPA tertiles. Nonobese individuals with lower levels of measured PA were insensitive to the nutritional manipulation of the preloads, suggesting a weaker satiety response to food. This study provides objective evidence that higher habitual PA improves acute homeostatic appetite control.

Habitual exercise is associated with cognitive control and cognitive reappraisal success.

Habitual exercise is associated with enhanced domain-general cognitive control, such as inhibitory control, selective attention, and working memory, all of which rely on the frontal cortex. However, whether regular exercise is associated with more specific aspects of cognitive control, such as the cognitive control of emotion, remains relatively unexplored. The present study employed a correlational design to determine whether level of habitual exercise was related to performance on the Stroop test measuring selective attention and response inhibition, the cognitive reappraisal task measuring cognitive reappraisal success, and associated changes in prefrontal cortex (PFC) oxygenation using functional near-infrared spectroscopy. 74 individuals (24 men, 50 women, age 18-32years) participated. Higher habitual physical activity was associated with lower Stroop interference (indicating greater inhibitory control) and enhanced cognitive reappraisal success. Higher habitual exercise was also associated with lower oxygenated hemoglobin (O2Hb) in the PFC in response to emotional information. However, NIRS data indicated that exercise was not associated with cognitive control-associated O2Hb in the PFC. Behaviorally, the findings support and extend the previous findings that habitual exercise relates to more successful cognitive control of neutral information and cognitive reappraisal of emotional information. Future research should explore whether habitual exercise exerts causal benefits to cognitive control and PFC oxygenation, as well as isolate specific cognitive control processes sensitive to change through habitual exercise.

Chronobiological assessment of habitual physical activity in humans in Western Siberia

The concept of typological variability of physiological individuality was a methodological basis for chrono-physiological assessment of habitual physical activity (HPA) and heart rate (HR) in individuals with different functional types of constitution (FTC) (low HPA (FTC-1), medium HPA (FTC-2), and high HPA (FTC-3)) living at different latitudes of West Siberia (Tyumen, 57°09’N; Khanty–Mansi Autonomous Okrug (KhMAO)–Yugra, 61°00’N; and Yamal–Nenets Autonomous Okrug (YaNAO), 63°12’N). The typical chronostructure of the circadian rhythm of HPA and HR was established for each FTC under the conditions of both mid-latitude (Tyumen) and northern regions. The regional differences were determined too. Compared to the mid-latitude parameters, the chrono-physiological assessment of typological variability of HPA and HR in FTC-1, FTC-2 and FTC-3 subjects living under the climatic and geographical conditions of KhMAO–Yugra and YaNAO in each respective group demonstrated a decrease in the midline-estimating statistic of rhythm (MESOR) and energy intensity of the circadian rhythm, an increase in the proportion of ultradian rhythms, differences in the time of HPA and HR acrophases, a decrease in synchronization and coherence indices, as well as a higher coefficient of the number of heart beats per locomotion and a lower circadian index. All of the above parameters of northerners with each FTC, with regard for the general principles of modern approaches, are not pathologies but rather regional characteristics that should be taken into consideration in the assessment of general state of health and prenosological diagnostics; they were the basis for using chronoprevention and time correction of reduced physical activity.

Exercise Training and Habitual Physical Activity: A Randomized Controlled Trial

Exercise training reduces adiposity and risk of cardiovascular disease. However, the combined effects of habitual free-living physical activity and aerobic training on waist circumference, weight, fitness, and blood pressure in postmenopausal women are unknown. To evaluate the effects of habitual physical activity levels during aerobic training on weight, waist circumference, fitness, and blood pressure. Secondary analysis of an RCT. Original data collected April 2001 to June 2005 and analyzed in 2012. Postmenopausal women in a supervised exercise trial. Women (n=325) were randomized to 4, 8, or 12 kcal/kg per week of aerobic training or a control group for 6 months. All outcome measures were collected at baseline and follow-up. Changes in dependent variables within each training group were evaluated across tertiles of pedometer-determined habitual physical activity outside exercise training sessions. Changes in waist circumference and weight. Reductions in waist circumference were significantly greater with higher steps/day accumulated outside exercise training compared to lower levels in the 4 (high: -4.8 cm vs low: -1.4 cm, p=0.03); 8 (high: -4.2 cm vs low: -0.4 cm, p=0.03), and 12 kcal/kg per week groups (high: -4.1 cm vs low: -0.7 cm, p=0.05). For all groups, p-trend≤0.03. A trend was observed for greater weight reduction with higher steps/day in the 4 kcal/kg per week group (p-trend=0.04) but not for the other exercise doses. No effects were observed for blood pressure or fitness measures (all p>0.05). In postmenopausal women, higher habitual physical activity while participating in aerobic training was associated with greater reductions in central adiposity, and was supportive of weight loss compared to lower levels.

Objective Habitual Physical Activity and Estradiol Levels in Obese Latina Adolescents

Lifetime physical activity (PA) is associated with decreased breast cancer (BC) risk; reports suggest that PA during adolescence contributes strongly to this relationship. PA lowers production of sex hormones, specifically estradiol, or decreases insulin resistance (IR), thereby lowering risk. Overweight Latina adolescents are insulin resistant and exhibit low levels of PA, potentially increasing their future BC risk. 37 obese Latina adolescents (15.7 ± 1.1 yrs) provided measures of PA using accelerometry; plasma follicular phase estradiol, sex-hormone binding globulin, total and free testosterone, dehydroepiandrosterone-sulfate (DHEAS); IR using HOMA-IR; and body composition via DEXA. Partial correlations and stepwise linear regressions assessed cross-sectional relationships between sex hormones, IR and PA. Body composition, and age were included a priori as covariates. Estradiol was negatively associated with accelerometer counts per minute (CPM; r = -0.4; P = .02), percent time spent in moderate PA (%MPA; r = -0.5; P = .006), and percent time in moderate or vigorous PA (%MVPA; r = -0.5; P = .007). DHEAS was positively associated with CPM (r = .4, P = .009), %MPA (r = .3, P = .04), and %MVPA (r = .3, P = .04). Other sex hormones and IR were not associated with PA measures. This study is the first to show that higher habitual PA was inversely associated with estradiol in obese adolescents.

Systemic analysis: Individual typological characteristics of the human body

Statistical analysis of the distribution of the mean somatometric, functional, and psychophysiological parameters in the total sample of subjects with the use of the χ2 and λ tests and low, medium, and high habitual physical activity (HPA) levels (LHPA, MHPA, and HHPA, respectively) at different ontogenetic stages (junior and senior school students and young adults of both sexes) showed wide quantitative and qualitative ranges of psychophysiological individuality in a healthy population and demonstrated that it is reasonable to distinguish three typological groups or functional constitutional types (FT-1 corresponding to LHPA; FT-2, to MHPA; and FT-3, to HHPA). Typical first- and second-order parameters, as well as the results of third-order tests characterizing the current state, were determined for each FT. In order to comprehensively assess the constitutional type (synthetic constitution) of the subjects with low, medium, and high HPAs, the integrated analysis of the set of their characteristics was performed using the principles of polythetic (multi-variate) classification. The results obtained using multivariate statistical methods confirmed the basic postulate of the concept of typological variability of physiological individuality that a healthy human population is qualitatively heterogeneous in morphological, functional, and psychophysiological traits. The integrated physiological and statistical analyses of the results provided a scientific basis for three functional constitutional types (FT-1, FT-2, and FT-3) corresponding to three synthetic constitutional types (C 0-1, C 00, and C 01). These data indicate that the systemic (constitutional) approach to the estimation of individual typological characteristics confirm a high informativeness of partial constitution (FT-1, FT-2, and FT-3) in the human biological organization, and the set of characters selected for analysis allows the synthetic constitutional types to be adequately differentiated on a formal basis.

Functional reserves and adaptive capacity of subjects with different levels of habitual physical activity

The basic characteristics of the cardiovascular system, physical capacity, and the degree of tension of regulatory mechanisms in the state of rest and under functional loading were identified on the basis of longitudinal studies in children of senior preschool and junior school ages, including boys and girls with low, medium, and high habitual physical activity (LHPA, MHPA, and HHPA). Analysis of the statistical distribution of traits using the χ2 and λ tests and the average statistical data on various functional indicators in the total sample identified a fairly wide area and qualitative differences in physiological individuality in a healthy population and the advisability of distinguishing three typological groups, i.e., functional types (FT-1, LHPA; FT-2, MHPA; FT-3, HHPA). The typological parameters of the first and second orders for each FT and performance test parameters of the third order describing the current functional state have been distinguished. Determination of the physiological features of FT-1, FT-2, and FT-3 with the establishment of their functional reserves and adaptive capacity permits the identification of different strategies of interaction between the body and the environment, estimation of their advantages and disadvantages, and a more reasonable approach to optimization of physical condition and premorbid diagnosis.

The concept of typological variability of physiological individuality: III. Psychophysiological characteristics of functional types differing in habitual physical activity

Results of longitudinal studies were used to estimate the psychophysiological characteristics of preschool and young school children and young adults of both sexes belonging to functional types (FTs) with low, medium, and high habitual physical activity (HPA) levels (FT-1, LHPA; FT-2, MHPA, and FT-3, HHPA, respectively). Statistical analysis of the distributions of averaged psychophysiological parameters in the total sample with the use of the χ2 and λ tests showed wide quantitative and qualitative ranges of psychophysiological individuality in a healthy population and demonstrated that it is reasonable to distinguish three typological groups (FT-1, FT-2, and FT-3). Typical first- and second-order parameters, as well as the results of third-order tests characterizing the current state, were determined for each FT. Determination of the psychophysiological characteristics of FT-1, FT-2, and FT-3 and their prevailing behavioral tendencies makes it possible to differentiate between strategies of organism-environment interaction and estimate their advantages and disadvantages.

The concept of typological variability of physiological individuality: II. Somatotype heterogeneity of population groups differing in habitual physical activity

Individual typological characteristics of habitual physical activity (HPA) in subjects of the preschool, primary school, and young adult ages were determined, and three functional types (FTs) comprising subjects with low, medium, and high HPAs (LHPA, MHPA, and HHPA, respectively) were distinguished (FT-1, FT-2, and FT-3, respectively). Subsequent comparison between the three groups of subjects showed that they differed in the ratio between the numbers of subjects with different morphological types (somatotypes). The results are at variance with the generally accepted notion on unidirectional changes in functional characteristics in the eurysomy-leptosomy series and permit a conceptual approach to the development of a partial (functional) scheme of constitution.

The concept of typological variability of physiological individuality: I. Intrapopulation diversity of human habitual physical activity and its typological estimation

A concept of typological variability of physiological individuality is suggested. In order to substantiate it, typological characteristics of individual variation in habitual physical activity (HPA) have been analyzed, at the first stage of the research, in subjects of both sexes at different ontogenetic stages (the preschool, primary school, adolescent, adult, and elderly ages). With the results of longitudinal studies taken into consideration, it has been demonstrated that HPA is a stable individual character in each age group and, in general, remains so in the course of ontogeny, as a subject changes age groups. This has made it possible to distinguish three functional types (FTs): subjects with low, medium, and high HPAs (FT-1, FT-2, and FT-3). An integrated approach to HPA assessment (pedometer measurements, daily electrocardiographic monitoring, a physical activity diary, and calculation of the circadian index) has allowed standards of daily physical activity and some functional characteristics of the cardiovascular system to be established in subjects of different FTs and prospects for further research in the assessment of individual health and the physiologically normal state to be determined on the basis of the new concept.

Physical activity in relation to energy intake and body fat in 8- and 13-year-old children in Sweden.

A random sample of 682 8- and 13-year-old children resident in Sweden was studied with regard to physical activity, energy intake, height, weight and skinfold thickness. A reduction of physical activity over the years was indicated by a tendency towards a higher body fat content in spite of a lower mean energy intake as compared with such values obtained 10-15 years ago in Swedish children of equal ages. Children characterized by high habitual physical activity tended to have a lower body fat content, despite a higher energy intake, than less active children. Children, especially girls, of parents with a low educational level showed a tendency towards higher body fat content as compared with those of parents with higher education.