“Excessive” pronation is often implicated as a risk factor for anterior knee pain (AKP). The amount deemed excessive is typically calculated using the means and standard deviations reported in the literature. However, when using this method, few studies find an association between pronation and AKP. An alternative method of defining excessive pronation is to use the joints’ available range of motion (ROM). The purposes of this study were to (1) evaluate pronation in the context of the joints’ ROM and (2) compare this method to traditional pronation variables in healthy and injured runners. Thirty-six runners (19 healthy, 17 AKP) had their passive pronation ROM measured using a custom-built device and a motion capture system. Dynamic pronation angles during running were captured and compared with the available ROM. In addition, traditional pronation variables were evaluated. No significant differences in traditional pronation variables were noted between healthy and injured runners. In contrast, injured runners used significantly more of their available ROM, maintaining a 4.21° eversion buffer, whereas healthy runners maintained a 7.25° buffer (P = .03, ES = 0.77). Defining excessive pronation in the context of the joints’ available ROM may be a better method of defining excessive pronation and distinguishing those at risk for injury.
Pedro Rodrigues, Trampas TenBroek and Joseph Hamill
Maria Laura Resem Brizio, Pedro C. Hallal, I-Min Lee and Marlos Rodrigues Domingues
The aim of this study was to investigate the association between lifetime physical activity and risk of lung cancer.
A case-control study was conducted in southern Brazil. Case subjects were recruited from oncology services of 4 hospitals. Control subjects were selected from the same hospitals, but from different services (traumatology and emergency). Both case subjects (n = 81) and control subjects (n = 168) were interviewed using a questionnaire about sociodemographic characteristics, anthropometric information and family history of cancer. Control subjects were matched to case subjects according to sex and age (± 5 years). Detailed information on smoking was collected. Physical activity was measured using the Lifetime Physical Activity Questionnaire.
Of the case subjects, 89% were either current or former smokers; among control subjects, this value was 57%. Participants in the second, third, and fourth quartiles of all-domains physical activity had odds ratios of 0.54 (95% CI, 0.21–1.40), 0.25 (95% CI, 0.08–0.72), and 0.24 (95% CI, 0.07–0.83) for lung cancer, compared with the lowest quartile, after adjusting for confounding. In the fully adjusted models, leisure-time physical activity was not associated with lung cancer risk.
Lifetime all-domains physical activity may reduce the risk of lung cancer.
Pedro Rodrigues, Ryan Chang, Trampas TenBroek, Richard van Emmerik and Joseph Hamill
Excessive pronation, because of its coupling with tibial internal rotation (TIR), has been implicated as a risk factor in the development of anterior knee pain (AKP). Traditionally, this coupling has been expressed as a ratio between the eversion range of motion and the TIR range of motion (Ev/TIR) that occurs during stance. Currently, this technique has not been used to evaluate specific injuries or the effects of sex. In addition, Ev/TIR is incapable of detecting coupling changes that occur throughout stance. Therefore, the purpose of this study was to compare the coupling between eversion and TIR in runners with (n = 19) and without AKP (n = 17) and across sex using the Ev/TIR ratio, and more continuously using vector coding. When using vector coding, significant coupling differences were noted in runners with AKP (34% to 38% stance), with runners with AKP showing relatively more TIR than eversion. Similarly significant differences were noted across sex (14%–25% and 36%–47% stance), with males transitioning from a loading to propulsive coordination pattern using a proximal to distal strategy, and female runners using a distal to proximal strategy. These differences were only detected when evaluating this coupling relationship using a continuous technique such as vector coding.
Trampas M. TenBroek, Pedro A. Rodrigues, Edward C. Frederick and Joseph Hamill
The purpose of this study was to: (1) investigate how kinematic patterns are adjusted while running in footwear with THIN, MEDIUM, and THICK midsole thicknesses and (2) determine if these patterns are adjusted over time during a sustained run in footwear of different thicknesses. Ten male heel-toe runners performed treadmill runs in specially constructed footwear (THIN, MEDIUM, and THICK midsoles) on separate days. Standard lower extremity kinematics and acceleration at the tibia and head were captured. Time epochs were created using data from every 5 minutes of the run. Repeated-measures ANOVA was used (P < .05) to determine differences across footwear and time. At touchdown, kinematics were similar for the THIN and MEDIUM conditions distal to the knee, whereas only the THIN condition was isolated above the knee. No runners displayed midfoot or forefoot strike patterns in any condition. Peak accelerations were slightly increased with THIN and MEDIUM footwear as was eversion, as well as tibial and thigh internal rotation. It appears that participants may have been anticipating, very early in their run, a suitable kinematic pattern based on both the length of the run and the footwear condition.
Felipe Fossati Reichert, Ana Maria Batista Menezes, Jonathan Charles Kingdom Wells, Ulf Ekelund, Fabiane Machado Rodrigues and Pedro Curi Hallal
Prospective studies on physical activity (PA), diet, and body composition in adolescents are lacking, particularly outside high-income countries.
To describe the methods used to assess these variables in the 1993 Pelotas (Brazil) Birth Cohort and to discuss the fieldwork challenges faced and alternatives to overcome them.
In 2006–07 a subsample of the 1993 Pelotas cohort was revisited. PA was estimated using questionnaires, a combined heart-rate and motion sensor (Acti-Heart), and the ActiGraph GT1M accelerometer. Diet was investigated by questionnaire. Total body water was determined by stable isotopes. Thirty individuals had their total energy expenditure assessed by doubly labeled water. All data were collected at participants’ home.
The logistics of the fieldwork and the difficulties in undertaking the study and alternatives to overcome them are presented. Preliminary analyses show that 511 individuals were traced (response rate = 90.0%). Compliance of both adolescents and their families for the motion sensors and body-composition measurements was excellent.
The authors conclude that it is feasible to carry out high-quality studies on PA in developing countries. They hope the article will be useful to other researchers interested in carrying out similar studies.
Pedro Curi Hallal, Felipe Fossati Reichert, Fernando Vinholes Siqueira, Samuel Carvalho Dumith, Juliano Peixoto Bastos, Marcelo Cozzensa da Silva, Marlos Rodrigues Domingues, Mario Renato Azevedo and Ulf Ekelund
The objective of this study was to evaluate physical activity (PA) levels in adults and their association with sex, age, and education level across categories of body mass index (BMI).
We conducted a population-based, cross-sectional study including 3100 individuals age ≥20 years living in Pelotas, Brazil. PA was assessed using the leisure-time section of the long International Physical Activity Questionnaire. “No PA” was defined as zero minutes of activity/week; “insuffcient PA” was defined as <150 minutes of activity/week; “high PA” was defined as ≥500 minutes of activity/week. BMI was categorized into normal (<25 kg/m2), overweight (25–29.9 kg/m2), and obesity (≥30 kg/m2).
The prevalence of insufficient PA was 71.6% among normal BMI subjects, 71.3% among overweight individuals, and 73.7% among obese ones (P = .67). No PA and high PA were also not associated with BMI. The associations between sex, age, and education level and PA levels tended to be stronger among normal-weight individuals compared with overweight and obese individuals. Among the obese, most associations were not significant. Among normal-weight individuals, higher PA levels were observed in men, young adults, and those with higher education.
Variables associated with leisure-time PA differed between normal-weight, overweight, and obese individuals. Studies on PA correlates might benefit from stratifying by BMI.