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Volume 34 (2024): Issue 3 (May 2024)

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Comparing Knee Kinetics and Kinematics in Healthy Individuals and Those With Knee Osteoarthritis, With and Without Flat Feet

Maryam Sohrabi, Giti Torkaman, and Fariba Bahrami

Individuals with knee osteoarthritis (KOA) and flat feet are more likely to experience increased pain and cartilage damage. This study aimed to investigate the knee kinetics, kinematics, pain, and physical function in individuals with moderate symptomatic KOA, in comparison to asymptomatic control participants. Thirty volunteers with moderate KOA (with flat feet n = 15, with normal feet n = 15) and 30 asymptomatic people (with flat feet n = 15, with normal feet n = 15) were evaluated. The knee adduction angular impulse, knee flexion moment, knee flexion angular impulse, and knee flexion angle were measured during level walking. The pain was assessed in patients with KOA. The study found that individuals with KOA had a significant increase in the knee adduction angular impulse compared with the asymptomatic people (P < .05). The KOA with flat feet group had significantly lower knee flexion moment, knee flexion angular impulse, and knee flexion angle values than the KOA with normal feet group (P < .05). Furthermore, the KOA with flat feet group had a higher pain score than the KOA with normal feet group. Individuals with osteoarthritis and flat feet had lower knee flexion moments which may indicate reduced knee force exerted through compensatory mechanisms. Despite this reduction, they reported significantly higher levels of pain compared with those without flat feet, a finding that warrants further investigation in future studies.

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Fourier Analysis of the Vertical Ground Reaction Force During Walking: Applications for Quantifying Differences in Gait Strategies

Taylor P. Trentadue and Daniel Schmitt

Time series biomechanical data inform our understanding of normal gait mechanics and pathomechanics. This study examines the utility of different quantitative methods to distinguish vertical ground reaction forces (VGRFs) from experimentally distinct gait strategies. The goals of this study are to compare measures of VGRF data—using the shape factor method and a Fourier series-based analysis—to (1) describe how these methods reflect and distinguish gait patterns and (2) determine which Fourier series coefficients discriminate normal walking, with a relatively stiff-legged gait, from compliant walking, using deep knee flexion and limited vertical oscillation. This study includes a reanalysis of previously presented VGRF data. We applied the shape factor method and fit 3- to 8-term Fourier series to zero-padded VGRF data. We compared VGRF renderings using Euclidean L2 distances and correlations stratified by gait strategy. Euclidean L2 distances improved with additional harmonics, with limited improvement after the seventh term. Euclidean L2 distances were greater in shape factor versus Fourier series renderings. In the 8 harmonic model, amplitudes of 9 Fourier coefficients—which contribute to VGRF features including peak and local minimum amplitudes and limb loading rates—were different between normal and compliant walking. The results suggest that Fourier series-based methods distinguish between gait strategies.

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Multi-Ingredient Preworkout Supplementation Compared With Caffeine and a Placebo Does Not Improve Repetitions to Failure in Resistance-Trained Women

Mariah Snyder, Christi Brewer, and Katrina Taylor

There has been an increase in the use of commercially available multi-ingredient preworkout supplements (MIPS); however, there are inconsistencies regarding the efficacy of MIPS in resistance-trained women. Purpose: To determine the effect of varying doses of MIPS compared with caffeine only (C) and a placebo (PL) on resistance-training performance in trained women. Methods: Ten women (21.5 [2.3] y) completed 1-repetition-maximum tests at baseline for leg press and bench press. A within-group, double-blind, and randomized design was used to assign supplement drinks (ie, PL, C, MIPS half scoop [MIPS-H], and MIPS full scoop [MIPS-F]). Repetitions to failure were assessed at 75% and 80% to 85% of 1-repetition maximum for bench and leg press, respectively. Total performance volume was calculated as load × sets × repetitions for each session. Data were analyzed using a 1-way repeated-measures analysis of variance and reported as means and SDs. Results: There were no differences in repetitions to failure for bench press (PL: 14.4 [3.2] repetitions, C: 14.4 [2.9] repetitions, MIPS-H: 14.2 [2.6] repetitions, MIPS-F: 15.1 [3.1] repetitions; P = .54) or leg press (PL: 13.9 [7.8] repetitions, C: 10.8 [5.9] repetitions, MIPS-H: 13.1 [7.1] repetitions, MIPS-F: 12.4 [10.7] repetitions; P = .44). Furthermore, there were no differences in total performance volume across supplements for bench press (PL: 911.2 [212.8] kg, C: 910.7 [205.5] kg, MIPS-H: 913.6 [249.3] kg, MIPS-F: 951.6 [289.6] kg; P = .39) or leg press (PL: 4318.4 [1633.6] kg, C: 3730.0 [1032.5] kg, MIPS-H: 4223.0 [1630.0] kg, MIPS-F: 4085.5 [2098.3] kg; P = .34). Conclusions: Overall, our findings suggest that caffeine and MIPS do not provide ergogenic benefits for resistance-trained women in delaying muscular failure.

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Erratum. Perceived Constraints to Pickleball Participation Among Black Older Adults

Journal of Aging and Physical Activity

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Strengthening Whole-of-School Physical Activity Models to Promote Physical Literacy: Moving Beyond a Component Approach

Paul Rukavina and Patricia Gremillion-Burdge

Whole-of-school approaches to physical activity and health promotion have the potential to promote physical literacy. However, for a variety of reasons there has not been widespread adoption of component whole-of-school frameworks to guide schools, such as the Comprehensive School Physical Activity Program. We argue that component frameworks have shortcomings and do not necessarily assist or support schools to take an approach that is consistent with how successful whole-of-school models or programs are created and built over time. In this paper, we argue that we need to apply guidance that resonates with stakeholders and stimulates schools to design their own unique whole-of-school physical activity model to provide equitable programming opportunities. We also present an argument on the need to incorporate improvement science and the use of social–ecological models to investigate the efficacy of this guidance model.

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Coingestion of Collagen With Whey Protein Prevents Postexercise Decline in Plasma Glycine Availability in Recreationally Active Men

Thorben Aussieker, Tom A.H. Janssen, Wesley J.H. Hermans, Andrew M. Holwerda, Joan M. Senden, Janneau M.X. van Kranenburg, Joy P.B. Goessens, Tim Snijders, and Luc J.C. van Loon

Whey protein ingestion during recovery from exercise increases myofibrillar but not muscle connective protein synthesis rates. It has been speculated that whey protein does not provide sufficient glycine to maximize postexercise muscle connective protein synthesis rates. In the present study, we assessed the impact of coingesting different amounts of collagen with whey protein as a nutritional strategy to increase plasma glycine availability during recovery from exercise. In a randomized, double-blind, crossover design, 14 recreationally active men (age: 26 ± 5 years; body mass index: 23.8 ± 2.1 kg·m−2) ingested in total 30 g protein, provided as whey protein with 0 g (WHEY), 5 g (WC05); 10 g (WC10), and 15 g (WC15) of collagen protein immediately after a single bout of resistance exercise. Blood samples were collected frequently over 6 hr of postexercise recovery to assess postprandial plasma amino acid kinetics and availability. Protein ingestion strongly increased plasma amino acid concentrations (p < .001) with no differences in plasma total amino acid availability between treatments (p > .05). The postprandial rise in plasma leucine and essential amino acid availability was greater in WHEY compared with the WC10 and WC15 treatments (p < .05). Plasma glycine and nonessential amino acid concentrations declined following whey protein ingestion but increased following collagen coingestion (p < .05). Postprandial plasma glycine availability averaged −8.9 ± 5.8, 9.2 ± 3.7, 23.1 ± 6.5, and 39.8 ± 11.0 mmol·360 min/L in WHEY, WC05, WC10, and WC15, respectively (incremental area under curve values, p < .05). Coingestion of a small amount of collagen (5 g) with whey protein (25 g) is sufficient to prevent the decline in plasma glycine availability during recovery from lower body resistance-type exercise in recreationally active men.

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The Midfoot Joint Complex (Foot Arch) Contributes to the Upper Body Position in Bipedal Walking and Coordinates With the Lower Limb Joints

Leonardo D. Barsante, Paula M.M. Arantes, Daniela V. Vaz, Fabricio A. Magalhães, Diego S. Carvalho, Aline C. Cruz, Renan A. Resende, Juliana M. Ocarino, Sérgio T. Fonseca, and Thales R. Souza

This study estimated the contribution of the midfoot joint complex (MJC) kinematics to the pelvis anterior–posterior positions during the stance phase of walking and investigated whether the MJC is functionally coordinated with the lower limb joints to maintain similar pelvic positions across steps. Hip, knee, ankle, and MJC sagittal angles were measured in 11 nondisabled participants during walking. The joints’ contributions to pelvic positions were computed through equations derived from a link-segment model. Functional coordination across steps was identified when the MJC contribution to pelvic position varied and the summed contributions of other joints varied in the opposite direction (strong negative covariations [r ≤ −.7] in stance phase instants). We observed that the MJC plantarflexion (arch raising) during the midstance and late stance leads the pelvis backward, avoiding excessive forward displacement. The MJC was the second joint that contributed most to the pelvis positions (around 18% of all joints’ contributions), after the ankle joint. The MJC and ankle were the joints that were most frequently coordinated with the other joints (≅70% of the stance phase duration). The findings suggest that the MJC is part of the kinematic chain that determines pelvis positions during walking and is functionally coordinated with the lower limb joints.

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Prepandemic Feasibility of Tele-Exercise as an Alternative Delivery Mode for an Evidence-Based, Tai Ji Quan Fall-Prevention Intervention for Older Adults

Dina L. Jones, Maura Robinson, Terry Kit Selfe, Lucinda Barnes, McKinzey Dierkes, Samantha Shawley-Brzoska, Douglas J. Myers, and Sara Wilcox

There is a critical need for fall-prevention interventions to reach medically underserved, hard-to-reach, rural older adults. The evidence-based Tai Ji Quan: Moving for Better Balance (TJQMBB) program reduces falls in older adults. This pre-COVID-19 pandemic study assessed the feasibility and impact of a 16-week tele-TJQMBB intervention in older adults. Instructors led six tele-TJQMBB classes via Zoom for 52 older adults (mean age ± SD 68.5 ± 7.7 years) at one academic and four community sites. Nearly all (97%) planned sessions were delivered. Average attendance was 61%. There were no adverse events. Fidelity was fair to good (mean 67%). Forty-one percent of sessions experienced technical disruptions. Participants improved their gait speed, balance, lower-extremity strength, and body mass index. Tele-TJQMBB was feasible with a positive impact on outcomes. This study was the first step toward establishing an additional delivery mode that could potentially expand TJQMBB’s reach and maintenance.

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Sport Science, Geopolitics, and How Each of Us Can Make a Difference

Jos J. de Koning, Carl Foster, David B. Pyne, Ralph Beneke, and Øyvind Sandbakk