A longitudinal examination of improved access on park use and physical activity in a low-income and majority African American neighborhood park.

This study sought to evaluate the impact of street crossing infrastructure modifications on park use and park-based physical activity in a low-income and African American community. A five-lane major highway created an access barrier between low-income housing units and the local neighborhood park in Columbia, Missouri. The installation of a signalized pedestrian crosswalk provided an opportunity to conduct a natural experiment to examine the effect of improved safe access upon community active living behaviors. Direct observation using SOPARC was collected prior to the crosswalk instillation in June 2012, after the crosswalk installation in June 2013 and again as a follow up in June 2014 during the same two-week period to assess changes in total park use and total energy expenditure by age, gender and race/ethnicity. Analysis of covariance models, controlling for temperature examined changes in total counts and total energy expenditure using pairwise Sidak post-hoc comparisons. Total park use increased from 2012 (n=2080) to 2013 (n=2275) and remained constant in 2014 (n=2276). However, despite increases in safe access and overall park use, there was a significant decrease in total energy expenditure following the installation of the crosswalk that was sustained in 2014. This study shows that increasing safe access to parks primarily positively influences park use but not park-based physical activity. While improved safe access is encouraging greater park use, there is a need for future research to examine additional factors such as social support, programming and environmental changes to engage community members in park-based physical activity.

Improvement in functional performance with high-speed power training in older adults is optimized in those with the highest training velocity.

PURPOSE: To identify whether variability in limb movement velocity during high-speed power training (HSPT) may impact physical functioning in older adults. METHODS: 42 older men and women (71.3 ± 6.6 years) were randomized to lower extremity HSPT (n = 28) or control (CON; n = 14) (Analysis 1) for 12 weeks. A second analysis (Analysis 2) allocated HSPT into high-velocity (n = 14) or low-velocity (n = 14) based on a limb movement speed above or below the median average velocity during the 12-week HSPT intervention. Habitual gait speed, maximal gait speed, timed up-and-go, and the short physical performance battery were measured at baseline and 12 weeks. Change scores were compared between HSPT and CON (Analysis 1), and high-velocity, low-velocity, and CON (Analysis 2) using ANCOVA. Statistical significance was accepted at p < 0.05. RESULTS: Analysis 1 There were no group differences in habitual gait speed, maximal gait speed, or timed up-and-go between HSPT and CON (all p > 0.05). Short physical performance battery was greater in HSPT (0.96 ± 0.19) compared to CON (0.10 ± 0.26; p = 0.01). Analysis 2 There were no group differences in the change in habitual GS (p = 0.33) among high-velocity, low-velocity and CON. There were significant group differences in the change in maximal GS (p = 0.007), timed up-and-go (p = 0.03), and short physical performance battery (p = 0.03). CONCLUSIONS: There is considerable variation in self-selected maximal limb velocity during HSPT in older adults. In the present cohort, an average limb velocity of 0.88 m/s during HSPT was necessary to ensure optimal improvement in functional performance for older adults, but this threshold will need further investigation.

Effect of Physical and Academic Stress on Illness and Injury in Division 1 College Football Players.

Stress-injury models of health suggest that athletes experience more physical injuries during times of high stress. The purpose of this study was to evaluate the effect of increased physical and academic stress on injury restrictions for athletes (n = 101) on a division I college football team. Weeks of the season were categorized into 3 levels: high physical stress (HPS) (i.e., preseason), high academic stress (HAS) (i.e., weeks with regularly scheduled examinations such as midterms, finals, and week before Thanksgiving break), and low academic stress (LAS) (i.e., regular season without regularly scheduled academic examinations). During each week, we recorded whether a player had an injury restriction, thereby creating a longitudinal binary outcome. The data were analyzed using a hierarchical logistic regression model to properly account for the dependency induced by the repeated observations over time within each subject. Significance for regression models was accepted at p ≤ 0.05. We found that the odds of an injury restriction during training camp (HPS) were the greatest compared with weeks of HAS (odds ratio [OR] = 2.05, p = 0.0003) and LAS (OR = 3.65, p < 0.001). However, the odds of an injury restriction during weeks of HAS were nearly twice as high as during weeks of LAS (OR = 1.78, p = 0.0088). Moreover, the difference in injury rates reported in all athletes during weeks of HPS and weeks of HAS disappeared when considering only athletes that regularly played in games (OR = 1.13, p = 0.75) suggesting that HAS may affect athletes that play to an even greater extent than HPS. Coaches should be aware of both types of stressors and consider carefully the types of training methods imposed during times of HAS when injuries are most likely.

The Impact of a Signalized Crosswalk on Traffic Speed and Street-Crossing Behaviors of Residents in an Underserved Neighborhood.

Infrastructure improvements such as pedestrian crosswalks that calm traffic and increase access to physical activity opportunities could alleviate important barriers to active living in underserved communities with outdated built environments. The purpose of this study was to explore how the built environment influences street-crossing behaviors and traffic speeds in a low-income neighborhood with barriers to active living in Columbia, Missouri. In 2013, a signalized pedestrian crosswalk and 400-ft-long median was constructed along a busy 5-lane, high-speed arterial highway linking low-income housing with a park and downtown areas. Data collection occurred prior to June 2012, and after June 2013, completion of the project at the intervention site and control site. Direct observation of street-crossing behaviors was performed at designated intersections/crosswalks or non-designated crossing points. Traffic volume and speed were captured using embedded magnetic traffic detectors. At the intervention site, designated crossings increased at the new crosswalk (p < 0.001), but not at non-designated crossings (p = 0.52) or designated crossings at intersections (p = 0.41). At the control site, there was no change in designated crossings (p = 0.94) or non-designated crossings (p = 0.79). Motor vehicles traveling above the speed limit of 35 mph decreased from 62,056 (46 %) to 46,256 (35 %) (p < 0.001) at the intervention site and increased from 57,891 (49 %) to 65,725 (59 %) (p < 0.001) at the control site. The installation of a signalized crosswalk facilitated an increase in safe street crossings and calmed traffic volume and speed in an underserved neighborhood. We believe these findings have significant public health implications that could be critical to advocacy efforts to improve infrastructure projects in similar communities.

High-speed power training in older adults: a shift of the external resistance at which peak power is produced.

Studies have shown that power training increases peak power (PP) in older adults. Evaluating the external resistance (% 1 repetition maximum [1RM]) at which PP is developed is critical given that changes in the components of PP (force and velocity) are dependent on the %1RM at which PP occurs. The purpose of this study was to compare the changes in PP (and the external resistance at which PP occurred) after 12 weeks of high-speed power training (HSPT) vs. traditional slow-speed strength training (SSST). Seventy-two older men and women were randomized to HSPT at 40% of the 1RM (HSPT: n = 24 [70.8 ± 6.8 years]); traditional resistance training at 80% 1RM (SSST: n = 22 [68.6 ± 7.8 years]); or control (CON: n = 18 [71.5 ± 6.1 years]). Measures of muscle performance were obtained at baseline and after the 12-week training intervention. Changes in muscle power and 1RM strength improved similarly with both HSPT and SSST, but HSPT shifted the external resistance at which PP was produced to a lower external resistance (from 67% 1RM to 52% 1RM) compared with SSST (from 65% 1RM to 62% 1RM) (p ≤ 0.05), thus increasing the velocity component of PP (change: HSPT = 0.18 ± 0.21 m·s; SSST = -0.03 ± 0.15 m·s) (p ≤ 0.05). Because sufficient speed of the lower limb is necessary for functional tasks related to safety (crossing a busy intersection, fall prevention), HSPT should be implemented in older adults to improve power at lower external resistances, thus increasing the velocity component of power and making older adults safer in their environment. These data provide clinicians with the necessary information to tailor exercise programs to the individual needs of the older adult, affecting the components of power.

The effect of fasting on indicators of muscle damage.

Many studies have tested the consumption of foods and supplements to reduce exercise-induced muscle damage, but fasting itself is also worthy of investigation due to reports of beneficial effects of caloric restriction and/or intermittent fasting on inflammation and oxidative stress. This preliminary investigation compared indicators of exercise-induced muscle damage between upper-body untrained participants (N=29, 22yrs old (SD=3.34), 12 women) who completed 8h water-only fasts or ate a controlled diet in the 8h prior to five consecutive laboratory sessions. All sessions were conducted in the afternoon hours (i.e., post meridiem) and the women completed the first session while in the follicular phase of their menstrual cycles. Measures of muscle pain, resting elbow extension, upper arm girth, isometric strength, myoglobin (Mb), total nitric oxide (NO), interleukin 1beta (IL1b), and tumor necrosis factor alpha (TNFa) were collected before and after eccentric contractions of the non-dominant elbow flexors were completed. The fasting group's loss of elbow extension was less than the post-prandial group (p<.05, eta(2)=.10), but the groups did not change differently across time for any other outcome measures. However, significantly higher NO (p<.05, eta(2)=.22) and lower TNFa (p<.001, eta(2)=.53) were detected in the fasting group than the post-prandial group regardless of time. These results suggest intermittent fasting does not robustly inhibit the signs and symptoms of exercise-induced muscle damage, but such fasting may generally affect common indirect markers of muscle damage.

Bike, walk, and wheel: a way of life in Columbia, Missouri, revisited.

BACKGROUND: In 2003, Columbia MO was the recipient of a Robert Wood Johnson Foundation (RWJF) Active Living by Design (ALbD) grant to foster active living in the community through behavioral (social marketing, education) and environmental change (improved street design standards, sidewalks around schools, activity-friendly infrastructure) strategies. PURPOSE: To examine the extent to which the ALbD intervention was associated with increased active living in children and adults community-wide. METHODS: Seasonal pedestrian and bicyclist counts were performed quarterly in January, April, July, and October at four intersections in downtown Columbia from 2007 to 2009. RESULTS: Pedestrian counts increased significantly during July 2009 and October 2009 compared to 2007 and 2008, whereas cyclist counts increased significantly during only July 2009 compared to 2007 and 2008. CONCLUSIONS: The ALbD intervention in Columbia was associated with modest increases in active living in the community, and continued evaluation of these behavior patterns is warranted. The combination of multiple strategies (social marketing, local programming, and infrastructure changes) may be a critical factor in improving active living in communities.

A Walking School Bus program: impact on physical activity in elementary school children in Columbia, Missouri.

BACKGROUND: The Robert Wood Johnson Foundation (RWJF) provided Columbia MO with an Active Living by Design (ALbD) grant in 2003 to promote active living in the community. A separate project was funded in 2006 through RWJF's Active Living Research program. PURPOSE: To evaluate whether participation in a Walking School Bus (WSB) program increased or decreased active living in elementary school children residing in Columbia, in association with ALbD funding. METHODS: Objective measures of physical activity obtained using accelerometers were collected over 7 days in children participating in a WSB program and children in a nonparticipating comparison group. Differences in the percentage of time spent in moderate- to vigorous-intensity exercise (%MVPA) were compared between groups. RESULTS: Children in WSB programs showed no differences in %MVPA compared to children not participating in the WSB; however, when comparing the relationship of %MVPA and age, the slope of the regression line was steeper for those children not participating in the WSB. CONCLUSIONS: The ALbD intervention in Columbia did not result in measurable changes in physical activity in children participating in the Walking School Bus program, but there was a negative association between age and physical activity, and the slope of that regression line was affected by participation in the program.

An evidence-based recommendation for the inclusion of specific local intrinsic factors in the study of knee osteoarthritis.

OBJECTIVE: Adequate characterization of the mechanical environment of the knee with osteoarthritis (OA) is important. These local intrinsic factors are difficult to measure and there is little evidence to guide their selection. This study makes an evidence-based recommendation for the inclusion of specific factors in the future study of knee OA. METHOD: Forty-six subjects with knee OA were examined. Observed function was measured by the Timed Chair Rise (TCR). Self-reported function was measured by the WOMAC Function Scale and pain was measured by the WOMAC Pain Scale. Local intrinsic factors measured included varus/valgus alignment, anterior/posterior (A/P) laxity, proprioception, isometric knee extension (KE) strength, isometric knee flexion (KF) strength, and knee range of motion (ROM). RESULTS: Factors were recommended for inclusion in future research if they were significantly correlated with at least one measure of function or pain and if the factor made a significant unique contribution to a regression model when more than one local intrinsic factor was correlated with the same measure of function or pain. Alignment was correlated with pain (r=0.48, p=0.001) and WOMAC function (r=0.38, p=0.009). A/P laxity was correlated with pain (r=0.30, p=0.04) and WOMAC function (r=0.37, p=0.01). Knee ROM was correlated to WOMAC function (r=-0.35, p=0.02). KE strength was correlated with TCR (r=0.32, p=0.03). Alignment made a significant contribution to prediction of pain (p=0.003). A/P laxity (p=0.004) and ROM (p=0.008) made a significant contribution to WOMAC function. CONCLUSION: We recommend future knee OA studies include the variables varus/valgus alignment, A/P laxity, ROM, and KE strength.

Effects of high-speed power training on muscle performance and braking speed in older adults.

We examined whether high-speed power training (HSPT) improved muscle performance and braking speed using a driving simulator. 72 older adults (22 m, 50 f; age = 70.6 ± 7.3 yrs) were randomized to HSPT at 40% one-repetition maximum (1RM) (HSPT: n = 25; 3 sets of 12-14 repetitions), slow-speed strength training at 80%1RM (SSST: n = 25; 3 sets of 8-10 repetitions), or control (CON: n = 22; stretching) 3 times/week for 12 weeks. Leg press and knee extension peak power, peak power velocity, peak power force/torque, and braking speed were obtained at baseline and 12 weeks. HSPT increased peak power and peak power velocity across a range of external resistances (40-90% 1RM; P < 0.05) and improved braking speed (P < 0.05). Work was similar between groups, but perceived exertion was lower in HSPT (P < 0.05). Thus, the less strenuous HSPT exerted a broader training effect and improved braking speed compared to SSST.

Effect of high-speed power training on muscle performance, function, and pain in older adults with knee osteoarthritis: a pilot investigation.

OBJECTIVE: To examine the effect of high-speed power training (HSPT) on muscle performance, mobility-based function, and pain in older adults with knee osteoarthritis. METHODS: Thirty-three participants (mean ± SD age 67.6 ± 6.8 years) were randomized to HSPT (n = 12), slow-speed strength training (SSST; n = 10), or control (CON; n = 11) for a 12-week intervention. HSPT performed 3 sets of 12-14 repetitions at 40% of the 1-repetition maximum (1RM) "as fast as possible," SSST performed 3 sets of 8-10 repetitions at 80% of the 1RM slowly, and CON performed stretching and warm-up exercises. Outcome measures included leg press (LP) 1RM and LP peak power (PP) from 40-90% of the 1RM and the corresponding PP velocity (PPV) and PP force; 400-meter walk, Berg Balance Scale, and timed chair rise; and self-reported function and pain using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Analysis of variance models were used to compare changes from baseline to 12 weeks. Statistical significance was accepted at P < 0.05. RESULTS: LP PP improved in both HSPT and SSST compared to CON (P = 0.04). LP PPV improved only in HSPT (P = 0.01). There were also improvements in timed chair rise (P = 0.002), WOMAC function (P = 0.004), and WOMAC pain (P = 0.02) across all of the groups. CONCLUSION: HSPT was effective at improving function and pain, but no more so than either SSST or CON. Because HSPT improved multiple muscle performance measures (strength, power, and speed), it is a more effective resistance training protocol than SSST and may increase safety in this population, especially when high-speed movements are required during daily tasks.

Rehabilitation of a surgically repaired rupture of the distal biceps tendon in an active middle aged male: a case report.

BACKGROUND: Complete rupture of the distal tendon of the biceps brachii is relatively rare and there is little information to guide therapists in rehabilitation after this injury. The purposes of this case report are to review the rehabilitation concepts used for treating such an injury, and discuss how to modify exercises during rehabilitation based on patient progression while adhering to physician recommended guidelines and standard treatment protocols. CASE PRESENTATION: The patient was an active 38-year old male experienced in weight-training. He presented with a surgically repaired right distal biceps tendon following an accident on a trampoline adapted with a bungee suspension harness. The intervention focused on restoring range of motion and strengthening of the supporting muscles of the upper extremity without placing undue stress on the biceps brachii. OUTCOMES: The patient was able to progress from a moderate restriction in ROM to full AROM two weeks ahead of the physician's post-operative orders and initiate a re-strengthening protocol by the eighth week of rehabilitation. At the eighth post-operative week the patient reported no deficits in functional abilities throughout his normal daily activities with his affected upper extremity. DISCUSSION: The results of this case report strengthen current knowledge regarding physical therapy treatment for a distal biceps tendon repair while at the same time providing new insights for future protocol considerations in active individuals. Most current protocols do not advocate aggressive stretching, AROM, or strengthening of a surgically repaired biceps tendon early in the rehabilitation process due to the fear of a re-rupture. In the opinion of the authors, if full AROM can be achieved before the 6(th) week of rehabilitation, initiating a slow transition into light strengthening of the biceps brachii may be possible. LEVEL OF EVIDENCE: 4-Single Case report.

A comparison of high-speed power training and traditional slow-speed resistance training in older men and women.

Muscle power, the product of force × velocity, is a critical determinant of function in older adults. Resistance training (RT) at high speed has been shown to improve peak muscle power in this population; however, different functional tasks may benefit from the improvement of power at values other than "peak" values, for example, tasks that require a greater velocity component or a greater force component. This study compared the effect of high-speed RT on muscle performance (peak power [PP] and its components [PP force and PP velocity] and overall peak velocity [VEL]) across a broad range of external resistances. Thirty-eight older men and women were randomized to high-speed power training at 40% of the 1-repetition maximum (1RM) (n = 13 [74.1 ± 6.4 years]); traditional RT at 80% 1RM (n = 13 [70.1 ± 7.0 years]); or control (n = 12 [72.8 ± 4.1 years]). Measures of muscle performance were obtained at baseline and after the 12-week training intervention. Muscle power and 1RM strength improved similarly with both high-speed and traditional slow-speed RT. However, speed-related muscle performance characteristics, PP velocity and overall VEL, were most positively impacted by high-speed power training, especially at lower external resistances. Because gains in speed-related measures with high-speed training compared to traditional RT do not come at the expense of other muscle performance outcomes, we recommend using an RT protocol in older adults that emphasizes high-speed movements at low external resistances.

The effect of autoregulatory progressive resistance exercise vs. linear periodization on strength improvement in college athletes.

Autoregulatory progressive resistance exercise (APRE) is a method by which athletes increase strength by progressing at their own pace based on daily and weekly variations in performance, unlike traditional linear periodization (LP), where there is a set increase in intensity from week to week. This study examined whether 6 weeks of APRE was more effective at improving strength compared with traditional LP in division I College football players. We compared 23 division 1 collegiate football players (2.65 +/- 0.8 training years) who were trained using either APRE (n = 12) or LP (n = 11) during 6 weeks of preseason training in 2 separate years. After 6 weeks of training, improvements in total bench press 1 repetition maximum (1RM), squat 1RM, and repeated 225-lb bench press repetitions were compared between the APRE and LP protocol groups. Analysis of variance (ANOVA) and analysis of covariance (ANCOVA) were used to determine differences between groups. Statistical significance was accepted at p < or = 0.05. Autoregulatory progressive resistance exercise demonstrated greater improvement in 1RM bench press strength (APRE: 93.4 +/- 103 N vs. LP: -0.40 +/- 49.6 N; ANCOVA: F = 7.1, p = 0.02), estimated 1RM squat strength (APRE: 192.7 +/- 199 N vs. LP: 37.2 +/- 155 N; ANOVA: F = 4.1, p = 0.05) and the number of repetitions performed at a weight of 225 lb (APRE: 3.17 +/- 2.86 vs. LP: -0.09 +/- 2.40 repetitions; ANCOVA: F = 6.8, p = 0.02) compared with the LP group over the 6-week training period. Our findings indicate that the APRE was more effective than the LP means of programming in increasing the bench press and squat over a period of 6 weeks.

Measurement of varus/valgus alignment in obese individuals with knee osteoarthritis.

OBJECTIVE: Frontal plane knee malalignment may increase progression of knee osteoarthritis (OA) and hasten functional decline. An accurate nonradiographic measure of knee alignment is necessary because the gold standard measure, the long-leg radiograph, is costly and often unavailable. Moreover, nonradiographic measures of knee alignment have not been validated in an obese population, where knee OA is common. The purpose of this study was to develop and assess the concurrent validity and reliability of a nonradiographic measure of frontal plane knee alignment and demonstrate the accuracy of the measure in an obese population. METHODS: Fifty-five subjects (41 women, 14 men; mean +/- SD age 62.9 +/- 10.3 years) with knee OA were examined. A nonradiographic measure (umbilical method) of frontal plane alignment, using the landmarks of the umbilicus, knee, and ankle, was compared with the radiograph gold standard. Statistical significance was accepted at P < 0.05. RESULTS: Eighty-nine percent of the participants had a body mass index (BMI) placing them in the overweight or obese category (mean +/- SD BMI for all subjects 31.3 +/- 6.1 kg/m(2)). Radiographic measures of alignment ranged from 9.1 degrees valgus to 14.3 degrees varus (76% of the participants had varus alignment, 12% had valgus alignment, and 2% had neutral alignment). Umbilical measures ranged from 1 degrees valgus to 21 degrees varus. The umbilical measure was significantly correlated with the radiographic method (r = 0.75, P < 0.001). The error of the umbilical measure was not significantly correlated with the BMI (r = -0.21, P = 0.13). CONCLUSION: The umbilical method of assessing frontal plane knee alignment is a valid surrogate for the radiographic gold standard and retains its accuracy in an obese population.

Bike, walk, and wheel: a way of life in Columbia, Missouri.

BACKGROUND: With funding support from the Robert Wood Johnson Foundation, the Active Living Partnership of Columbia, Missouri, sought to make routine physical activity more commonplace in the community through behavioral and environmental change strategies. INTERVENTION: The Active Living by Design 5P model (partnerships, promotions, programs, policy changes, and physical projects) was modified to create two mutually reinforcing components. Programs and promotions (e.g., Walking School Bus) were implemented to influence individual behaviors and generate public policy advocates. Policy changes, such as activity-friendly street design standards, created safe and attractive places for physical activity programs. A strong, diverse community partnership supported all efforts. RESULTS: Key project successes were a citywide social marketing program; the Walking School Bus program, which grew rapidly; and policy campaigns resulting in improved street design standards and a voter-approved $3.5 million sales tax for sidewalks around schools. Notable challenges included programs targeting teenagers and efforts to increase physical activity through self-reported activity logging. LESSONS LEARNED: The most important lesson was to implement multiple strategies because programs can leverage policy successes, and new policies often lead to more funding for infrastructure. Other lessons learned were to build early successes by reaching first for the "low-hanging fruit" (e.g., elementary-age children rather than teenagers) and to have a flexible plan to take advantage of unexpected opportunities (e.g., a new, influential partner with a specific interest). CONCLUSIONS: A modified 5P model was tested and found to be an effective framework for achieving behavioral and environmental changes that promote healthy, active lifestyles in the community.

Accuracy of a non-radiographic method of measuring varus/valgus alignment in knees with osteoarthritis.

Knee alignment has been shown to affect incidence, progression and treatment of knee osteoarthritis (OA). The gold standard for measuring alignment is a radiograph that is often difficult to obtain. This study demonstrates that a clinical non-radiographic measure can serve as a surrogate assessment of knee alignment in older adults with knee OA. We believe these findings will allow more widespread evaluation of one critical mechanical factor essential to the study of knee OA.

The effect of a high-intensity interval training program on high-density lipoprotein cholesterol in young men.

This study examined the impact of an 8-week program of high-intensity interval training on high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and the atherogenic index (TC/HDL-C) in 36 untrained men ages 21-36 years. Participants were randomly assigned to an interval training group (n = 20) or a control group (n = 16). Participants in the experimental group performed 3.2 km of interval running (1:1 work:rest ratio) 3 times a week for 8 weeks at an intensity of 90% of maximal heart rate ( approximately 423 kcal per session). Results indicated significant pre- to posttraining changes in HDL-C (1.1 vs. 1.3 mmolxL, p < 0.0001) and TC/HDL-C (3.8 vs. 3.1, p < 0.0001) but no significant changes in TC (3.9 vs. 3.8 mmolxL, p > 0.05) with interval training. It was concluded that an 8-week program of high-intensity interval training is effective in eliciting favorable changes in HDL-C and TC/HDL-C but not TC in young adult men with normal TC levels. Our findings support the recommendations of high-intensity interval training as an alternative mode of exercise to improve blood lipid profiles for individuals with acceptable physical fitness levels.