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SummaryBackground Parental obesity is a known determinant of childhood obesity. Previous research has shown a strong maternal influence on body mass index (BMI) during infancy and early childhood. Objectives The purpose of this research was to investigate the BMI associations between mother and offspring from birth to age 18 years. Methods Participants were selected from the Fels Longitudinal Study. The current study sample includes 427 (215 mother/son and 212 mother/daughter) mother/child pairs. These pairs are repeatedly measured at multiple age groups in children, resulting in a total of 6,263 (3,215 mother/son, 3,048 mother/daughter) observations for data analysis. Inclusion criteria were children with measured height and weight for BMI collected at ages 0 to 18 years and their mother with BMI data. Maternal influences of BMI on offspring BMI from birth to early adulthood were analyzed by Spearman correlations and linear regression analyses. Results Mother/son BMI correlations became statistically significant (p ≤ 0.05) at age 5–6 years and were significant through puberty and into early adulthood at age 18 years. Mother/daughter correlations became significant at age 1.5 years and also continued through adolescence, puberty and early adulthood at age 18 years. Associations persisted after the study sample was grouped into life stages and adjusted for decade of birth and parity. Conclusions The mother/daughter relationship was more strongly correlated than the mother/son relationship and also became statistically significant at an earlier age than boys.

Recently, a fitness competition called the Pump and Run (PR) has been popularized. Composed of 2 events, a 5-km road race time (RT) in seconds and a maximal-repetition bench press (BPR) with resistance based on a percentage of body mass (M), the final score (RTadj) equals RT - 30(BPR). From published findings, the authors hypothesized that the PR would impose a bias against heavier competitors. Furthermore, the potential for age bias in this event has not been evaluated. Therefore, the purpose of this study was to investigate M and age bias in the PR for men and women. For 74 female and 343 male competitors in a large PR event, RT, BPR, M, and age were collected from official competition results. Two subsamples were randomly created from the original sample: the validation (VAL) (54 women and 258 men) and the cross-validation (CVAL) (20 women and 85 men). For the VAL sample, the RTadj showed significant bias against heavier runners (women r = 0.35; men r = 0.28; P0.01 for both) but no age bias (women r = 0.04; men r = 0.005; P0.05 for both). Using allometric modeling, the authors developed a set of M-based correction factors to be multiplied by each RTadj to yield new adjusted run times (NRTadj) that would be free of M bias. As applied to the CVAL sample, the NRTadj values virtually eliminated the M bias (women r = 0.04; men r = 0.002; P0.05 for both) of the current PR scoring system and retained the absence of age bias (women r = 0.02; men r = 0.0002; P0.05 for both). The authors recommend the use of the NRTadj scores for future PR competitions.

The adverse effect of increasing age and/or body weight on distance run performance has been well documented. Accordingly, nearly all five kilometer (5K) road races employ age categories and, sometimes, a heavier body weight classification. Problems with such conventions include small numbers of runners within older age categories and the advantage given to the lightest runners within each weight category. We developed a 5K Handicap (5KH), a model that calculates an adjusted run time based on the inputs of actual 5K run time, age, and body weight for men and women. This adjusted time, then, can be compared between runners of different ages and body weights. The purpose of this paper was to explain, in detail, the derivation of the 5KH formula using published theoretical and empirical findings on age, body weight and distance run time relationships. To our knowledge, the 5KH is the first such model and overcomes the problems associated with being heavier within one weight class and having too few runners i...

Backwards running (BR) results in greater cardiopulmonary response and muscle activity compared with forward running (FR). BR has traditionally been used in rehabilitation for disorders such as stroke and lower leg extremity injuries, as well as in short bursts during various athletic events. The aim of this study was to measure the effects of sustained backwards running training on forward running economy in trained male athletes. Eight highly trained, male runners (26.13 ± 6.11 years, 174.7 ± 6.4 cm, 68.4 ± 9.24 kg, 8.61 ± 3.21% body fat, 71.40 ± 7.31 ml·kg-1·min-1) trained with BR while harnessed on a treadmill at 161 m·min-1 for 5 weeks following a 5-week BR run-in period at a lower speed (134 m·min-1). Subjects were tested at baseline, postfamiliarized, and post-BR training for body composition, a ramped V[Combining Dot Above]O2max test, and an economy test designed for trained male runners. Subjects improved forward running economy by 2.54% (1.19 ± 1.26 ml·kg-1·min-1, p = 0.032) at 215 m·min-1. V[Combining Dot Above]O2max, body mass, lean mass, fat mass, and % body fat did not change (p > 0.05). Five weeks of BR training improved FR economy in healthy, trained male runners without altering V[Combining Dot Above]O2max or body composition. The improvements observed in this study could be a beneficial form of training to an already economical population to improve running economy.

Lateral foot wedges represent a biomechanical intervention aimed at reducing medial knee loads. However, the effects of varying wedge amounts on biomechanical variables and orthotic comfort have not been systematically studied. Further, arch height may influence the comfort of laterally wedged devices. Therefore, the primary purpose of this study was to examine the effect of incrementally increasing lateral wedge amounts on knee adduction moment parameters and subjective comfort. The secondary purpose was to relate arch height measures to the comfort of the devices.Twenty-five healthy subjects underwent three-dimensional instrumented gait analysis testing using seven inclinations of lateral wedging (0°, 2°, 4°, 6°, 8°, 10°, 12°). Subjects reported comfort level for each orthotic condition. Arch heights were measured in standing and sitting, and rigidity index and stiffness were calculated.The knee adduction moment decreased with wedge amounts up to 6°, but more aggressive amounts did not yield additional reductions. Comfort ratings did not change from baseline until wedge amounts exceeded 8°. In addition, arch height measures, arch rigidity index and stiffness did not relate to the comfort of the orthotic device regardless of the wedge amount.Knee adduction moment decreased with mild wedge amounts while maintaining comfort. Wedge amounts greater than 6° yielded little additional mechanical benefit and amounts greater than 8° compromised comfort. It appears that 4°-6° of lateral wedging are optimal in regard to desirable biomechanical change and comfort level in healthy individuals.

The metabolic cost and cognitive demand of altering natural gait have not been well studied. The purpose of this investigation was to assess three modified patterns - toe out, ipsilateral trunk lean and a medial weight shift at the foot - on the basis of 1) medial knee joint load reduction, 2) metabolic cost of performance and 3) subject perception of task difficulty.12 healthy individuals underwent 3 dimensional motion analysis and metabolic testing to assess the gait mechanics and energy expenditure of natural gait and the three experimental gait patterns, performed to a self-selected moderate degree. Walking speed was controlled. Perceived workload was assessed using the NASA Task Load Index.Trunk lean significantly reduced first peak knee adduction moment (↓32%, P0.001) as well as KAM impulse (↓35%, P0.001), but was costly in terms of energy expenditure (↑11%, P0.001) and perceived workload (↑1178%, P0.001). A moderate toe-out pattern significantly reduced the second peak knee adduction moment (↓32%, P0.001) and KAM impulse (↓14%, P=0.026), but had no effect on the first peak. Conversely, toe-out was least demanding in terms of additional energy expenditure (↑2%, P=0.001) and perceived workload (↑314%, P=0.001). Medial shift did not reduce knee adduction moment.The prioritization of joint load reduction versus additional metabolic and cognitive demands could play a substantial role in the clinical decision making process of selecting a modified gait pattern.

Background and purpose: Strength and range of motion of the foot and ankle have been shown to be related to measures of balance and fall risk in older adults. The primary purpose of this pilot investigation was to evaluate the feasibility of a 6-week home-based exercise program focusing on the foot and ankle and any associated changes in balance, muscle performance and range of motion in older adults. Methods: This single-group repeated measures study involved a convenience sample of 21 healthy communitydwelling older adults age 60-90. Nineteen participants completed all phases of the testing and training. The intervention was a 6-week home-based exercise program focusing on ankle musculature performed 3 times per week. Outcome measures were assessed on three separate occasions: baseline, pre-intervention, and post-intervention. Outcome measures included the Mini-Balance Evaluation Systems Test (Mini-BESTest), gait speed, Timed Up and Go (TUG), Activities Specific Balance Confidence Scale (ABC), gastrocnemius muscle strength and ankle dorsiflexion range of motion. Results: Following the intervention, there were significant improvements in the Mini-BESTest, gait speed, TUG, gastrocnemius strength and ankle dorsiflexion range of motion. There was also significant positive relationship between improvements in the Mini-BESTest and gastrocnemius strength. There were no unanticipated adverse events and compliance was high. Conclusions: A simple but progressive home-based exercise program for the foot and ankle appears to be feasible for older individuals and may lead to meaningful improvements in measures of balance and mobility. Further research of this targeted intervention may be warranted.

Crecelius, AR, Vanderburgh, PM, and Laubach, LL. Contributions of body fat and effort in the 5K run: age and body weight handicap. J Strength Cond Res 22(5): 1475-1480, 2008-The 5K handicap (5KH), designed to eliminate the body weight (BW) and age biases inherent in the 5K run time (RT), yields an adjusted RT (RTadj) that can be compared between runners of different BW and age. As hypothesized in a validation study, however, not all BW bias may be removed, because of the influences of body fatness (BF) and effort (run speed; essentially the inverse as measured by rating of perceived exertion (RPE)). This study's purpose was to determine the effects of BF and RPE on BW bias in the 5KH. For 99 male runners in a regional 5K race (age = 43.9 +/- 12.1 years; BW = 83.4 +/- 12.9 kg), BF was determined via sum of three skinfolds just before the race. RPE, on the 20-point Borg scale, was used to assess overall race effort on race completion. Multiple regression analysis was used to develop a new adjusted RT (NRTadj, the RTadj corrected for BF and RPE), which was computed for each runner and then correlated with BW to determine bias. Indicative of slight bias, BW was correlated with RTadj (r = 0.220, p = 0.029). Both BF (p = 0.00002) and RPE (p = 0.0005) were significant, independent predictors of RTadj. NRTadj was not significantly correlated with BW (r = 0.051, p = 0.61), but BF explained 90%, and RPE explained only 6%, of the remaining BW bias evidenced in the 5KH. The previous finding that the 5KH does not remove all BW bias is apparently accounted for by BF and not RPE. Because no handicap should be awarded for higher BF, this finding suggests that the 5KH, for men, appropriately adjusts for the age and BW vs. RT biases previously noted

(1990). Gold Medal Volleyball: The Training Program and Physiological Profile of the 1984 Olympic Champions. Research Quarterly for Exercise and Sport: Vol. 61, No. 2, pp. 196-200.

(2002). Effects of Two Different Strength Training Modes on Motor Performance in Children. Research Quarterly for Exercise and Sport: Vol. 73, No. 3, pp. 340-344.

This study compared the caloric expenditure of 30 consecutive minutes (30 minute) of moderate intensity walking with 3 intermittent 10-minute bouts (3 x 10 minutes) of moderate intensity walking in healthy, unfit men (40-49 years). Screening consisted of VO(2)max testing, which was measured using the Balke graded exercise test. Criteria for participation in this study included a measured VO(2)max less than 33.8 ml.kg(-1).min(-1) (

Effects of a 10 wk, three times per wk individualized bicycle ergometer training program were investigated in 16 healthy sedentary women 19–29 yr-old who were not taking oral contraceptives or other medications. Twelve women were in an interval type program, 6 in a continuous program, all performing 30 min exercise per session at 70% maximum heart rate reserve. Conditioning responses did not differ between the training regimens. Training produced increases in maximum oxygen uptake and physical work capacity. Percent body fat determined by underwater weighing was significantly reduced as was resting heart rate, after the training program. Maximum heart rate was unchanged. Despite changes in “fitness” variables, post-training values of high density lipoprotein cholesterol and triglycerides did not differ from pretraining. High-density lipoprotein cholesterol was significantly reduced at 2 and 5 wk of training and returned to control levels at 10 wk. Exercise conditioning leading to improved physical fitness in healthy women may not be associated with increments in high density lipoprotein cholesterol levels.

The effects of a 10-wk individualized bicycle ergometer interval training program were investigated in a group of 13 sedentary women on a specific oral contraceptive (50 micrograms mestranol, 1 mg norethisterone) to determine if, like men on physical training, their high-density lipoprotein cholesterol levels would increase. Six additional women on the oral contraceptive served as a nonexercising control group. All subjects were between 18 and 30 yr and were nonsmokers. Diet and alcohol intake were stable throughout the study period, and were monitored throughout. The interval training program was three times per week, 30-min exercise per session, at 70% maximum heart rate reserve (resting heart rate + 0.7 x [maximum heart rate-resting heart rate]). Training produced increases (p0.05) in maximum oxygen uptake. Body weight was unchanged. However, unlike similar training programs with males, there were no significant changes in plasma high-density lipoprotein cholesterol or triglycerides. In women receiving estrogen progestin oral contraceptives, consistent exercise programs may fail to elevate high density lipoprotein cholesterol levels, consistent with an interaction of sex hormone-exercise effects and/or with the less marked effect of exercise on high-density lipoprotein cholesterol in women.The effects of a 10 week individualized bicycle ergometer interval training program were investigated in a group of 13 sedentary women on a specific (OC) oral contraceptive (50 mg mestranol, 1 mg norethisterone) to determine if, like men on physical training, their (HDL) high-density lipoprotein cholesterol levels would increase. 6 additional women on OCs served as a nonexercising control group. All subjects were between 18 and 30 years and were nonsmokers. Diet and alcohol intake were stable throughout the study period, and were monitored throughout. The interval training program was 3 times/week, 30 minutes exercise/session, at 70% maximum heart rate reserve (resting heart rate + 0.7 x [maximum heart rate-resting heart rate]). Training produced increases (p0.05) in maximum oxygen uptake. Body weight was unchanged. However, unlike similar training programs with males, there were no significant changes in plasma HDL cholesterol or triglycerides. In women receiving estrogen progestin OCs, consistent exercise programs may fail to elevate HDL cholesterol levels, consistent with an interaction of sex hormone-exercise effects and/or with the less marked effect of exercise on HDL cholesterol in women.

Fourteen flexibility measurements, 63 direct and derived anthropometric measurements, and the somatotypes of 63 college men, mean age of 19.0 years, were obtained in order to assess the relationships between flexibility and anthropometric measurements, anthropometric measurements and somatotypes, and flexibility and somatotype. The correlations between the flexibility measurements and the anthropometric measurements were low and mostly insignificant. Body fat, as measured by skinfold calipers, yielded fairly high significant negative correlations with the flexibility measurements. The correlations between the flexibility measurements and somatotype were insignificant. Generally high correlation coefficients were obtained between the anthropometric measurements and somatotype.

In order to discover whether statistically significant differences exist between measurements taken on the right and left sides of the body, 21 such anthropometric dimensions were compared. In eight cases significant differences were found. Six of these dealt with the forelimb, in which the dimension measured on the right side was greater. Since data on handedness is lacking, we do not know whether this is related to the handedness of the subjects.

To study relative stresses of wheelchair activity, seven able-bodied subjects' metabolic (oxygen uptake) and cardiopulmonary (heart rate and pulmonary ventilation) responses were determined during wheelchair (arm stroking) and bicycle (leg pedaling) exercise at identical propulsion velocities and work rates. For this, subjects exercised on a combination wheelchair-bicycle ergometer at wheel velocities of 1.17, 2.34, and 3.51 km/hr. The six bouts of exercise were intennittent~5-min exercise periods interspersed by 10-min rest periods. At 1.17 km/hr, no significant differences were found between wheelchair and bicycle exercise for each of the monitored variables. At 2.34 and 3.51 km/hr, however, all responses were significantly higher for wheelchair exercise. At these higher velocities, calculated respiratory exchange ratio and ventilatory equivalent values were also significantly higher for wheelchair exercise. These results suggest that acute exposure to wheelchair activity could be relatively stressful and could limit rehabilitative efforts.

(1974). A Proposed Standard Procedure for Static Muscle Strength Testing. American Industrial Hygiene Association Journal: Vol. 35, No. 4, pp. 201-206.

The purpose of this study was to develop a wheelchair ergometer (WERG) test to evaluate fitness for manual wheelchair activity. Thirty able-bodied females participated in a progressive intensity, discontinuous test where exercise bouts were 4 min in duration interspersed with 5-min rest periods. Physiological responses of oxygen uptake (VO2), respiratory exchange ratio (R), net mechanical efficiency (ME), pulmonary ventilation (VO) and heart rate (HR) were determined during the final minute of exercise at power output (PO) levels of 30, 60, 90, 120 and 150 kpm/min. These responses were generally found to be linearly related to PO, however, net ME initially increased with PO and plateaued at approximately 11 per cent at 90 kpm/min. Criteria for fitness evaluation were based upon: (1) magnitude of physiological responses at each PO level; and (2) the maximal PO level completed.

Experiments were conducted to measure static muscular strength characteristics of women subjects and compare these results with similar data previously reported for males. Twelve measures of static muscular strength, 22 body-size measurements, and the somatotypes of 31 female subjects were investigated. Selected reports in the literature that have dealt with the comparison of static and dynamic muscular strength of women and men are presented and discussed in some detail. The summary descriptive statistics for the strength measures were compared (tabularly and graphically) and percentage differences in strength between women and men reported. An analysis of the range and the average mean percentage difference in muscular strength capabilities is presented. The complete intercorrelation matrix for the 38 variables (including age) obtained in this research is shown.

An anthropometric survey of U. S. Army women was conducted during the winter of 1976-1977--the first such survey in 30 years. The survey was planned and carried out in response to the need for current and comprehensive body size and strength data for the women who make up an increasingly large part of the U. S. Army. The main purpose of the survey was to obtain and develop statistical data on body size, workspace parameters, and static muscle strength of U. S. Army women. During the survey, data were obtained on 128 conventional body size dimensions, 14 workspace dimensions, and 9 static strength measurements. Many of the measurements made had not been previously reported for any large-scale survey of women, military or civilian. Other measurements were selected to supplement and complement data already available to provide up-to-date information for use in the design of clothing, protective equipment, workspace and industrial equipment which women in the Army wear, use, operate, or within which they work. This, the first of a series of reports dealing with this survey, describes the methodology used in the conduct of the survey. Included here are an outline of the survey design, a listing of the landmarks used in defining the dimensions to be measured and detailed descriptions of the procedures used in making each measurement. Measurement techniques used in previous large-scale anthropometric surveys of women also are listed here. Thus this report, in addition to reporting the methodology of the present survey, constitutes a comprehensive source book of anthropometric techniques for use with women.

A technique was developed that enables precisely specified ear dimensions to be measured directly from PhotoMetriC slides. Summary statistics for each of the various ear dimensions are presented for a sample of 500 subjects randomly chosen from a total series of 2236 photographic slides collected during the 1957 Authropometric Survey of USAF Male Flying Personnel. Regression equations for predicting the various ear dimensions from Ear Length and Ear Breadth are presented. A complete intercorrelation matrix for all variables studied in this research is also shown. The reliability and objectivity of the technique are discussed.

Thirteen measures of static strength, 13 body-size measurements, and the somatotypes of 77 male subjects were obtained and the interrelationships among these measures were investigated. Summary descriptive statistics are given for the 29 variables studied. Simple and selected partial correla