Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central—O2 delivery and transportation to the working muscles—or peripheral factors—O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers’ behavior in competition and to develop efficient training programs.
Ana Sousa, Pedro Figueiredo, David Pendergast, Per-Ludvik Kjendlie, João P. Vilas-Boas and Ricardo J. Fernandes
Philip W. Fink, Sarah P. Shultz, Eva D’Hondt, Matthieu Lenoir and Andrew P. Hills
, participants were instructed to look at a black dot placed 2 m away, while in the eyes closed condition, participants were instructed to keep their eyes closed for the entire trial. Trials were randomized for visual condition, and COP was measured using a plantar pressure distribution measuring device (EMED
Sarah P. Shultz, Jinsup Song, Andrew P. Kraszewski, Jocelyn F. Hafer, Smita Rao, Sherry Backus, Rajshree M. Hillstrom and Howard J. Hillstrom
were measured using (E) a custom jig. Foot function was assessed using (F) a plantar pressure measuring device. Plantar pressure distribution includes center of pressure excursion (gray line). Images reprinted, with permission, from Joshi R, Song J, Mootanah R, Rao S, Backus SI, Hillstrom HJ. Structure
James C. Martin, Christopher J. Davidson and Eric R. Pardyjak
Sprint-cycling performance is paramount to competitive success in over half the world-championship and Olympic races in the sport of cycling. This review examines the current knowledge behind the interaction of propulsive and resistive forces that determine sprint performance. Because of recent innovation in field power-measuring devices, actual data from both elite track- and road-cycling sprint performances provide additional insight into key performance determinants and allow for the construction of complex models of sprint-cycling performance suitable for forward integration. Modeling of various strategic scenarios using a variety of field and laboratory data can highlight the relative value for certain tactically driven choices during competition.
Jonathan Sinclair, Sarah J. Hobbs, Paul J. Taylor, Graham Currigan and Andrew Greenhalgh
In running analyses where both kinetic and kinematic information is recorded, participants are required to make foot contact with a force and/or pressure measuring transducer. Problems arise if participants modify their gait patterns to ensure contact with the device. There is currently a paucity of research investigating the influence of different underfoot kinetic measuring devices on 3-dimensional kinematics of running. Fifteen participants ran at 4.0 m/s in four different conditions: over a floor embedded force plate, Footscan, Matscan, and with no device. Three-dimensional angular kinematic parameters were collected using an eight camera motion analysis system. Hip, knee, and ankle joint kinematics were contrasted using repeated-measures ANOVAs. Participants also rated their subjective comfort in striking each of the three force measuring devices. Significant differences from the uninhibited condition were observed using the Footscan and Matscan in all three planes of rotation, whereas participants subjectively rated the force plate significantly more comfortable than either the Footscan/Matscan devices. The findings of the current investigation therefore suggest that the disguised floor embedded force plate offers the most natural running condition. It is recommended that analyses using devices such as the Footscan/Matscan mats overlying the laboratory surface during running should be interpreted with caution.
Gary L. Harrelson, Deidre Leaver-Dunn, A. Louise Fincher and James D. Leeper
The purpose of this study was to examine the inter- and intratester reliability of lower extremity circumference measurements obtained by two testers using the same tape measure and two different tape measures. Twenty-one male high school student-athletes participated in this study. Two testers measured lower extremity circumference at three sites using a standard flexible tape measure and a Lufkin tape measure with a Gulick spring-loaded handle attachment. Measurement sites were medial joint line, 20 cm above medial joint line, and 15 cm below medial joint line. Intraclass correlation coefficients were computed for inter- and intratester comparisons for each measuring device and each measurement site. Results indicated high reliability but a significant difference between the two tape measures. These findings indicate that the reliability of lower extremity circumference measurements is not influenced by tester experience and that the Lufkin tape measure with the Gulick handle attachment is the more accurate of the two tape measures.
Johnny E. Nilsson and Hans G. Rosdahl
The purpose was to develop and validate portable force-measurement devices for recording push and pull forces applied by each foot to the foot bar of a kayak and the horizontal force at the seat. A foot plate on a single-point force transducer mounted on the kayak foot bar underneath each foot allowed the push and pull forces to be recorded. Two metal frames interconnected with 4 linear ball bearings, and a force transducer allowed recording of horizontal seat force. The foot-bar-force device was calibrated by loading each foot plate with weights in the push–pull direction perpendicular to the foot plate surface, while the seat-force device was calibrated to horizontal forces with and without weights on the seat. A strong linearity (r 2 = .99–1.0) was found between transducer output signal and load force in the push and pull directions for both foot-bar transducers perpendicular to the foot plate and the seat-force-measuring device. Reliability of both devices was tested by means of a test–retest design. The coefficient of variation (CV) for foot-bar push and pull forces ranged from 0.1% to 1.1%, and the CV for the seat forces varied from 0.6% to 2.2%. The current study opens up a field for new investigations of the forces generated in the kayak and ways to optimize kayak-paddling performance.
Greg Petrucci Jr., Patty Freedson, Brittany Masteller, Melanna Cox, John Staudenmayer and John Sirard
Purpose: Determine the sensitivity of the Misfit Shine™ (MS) to detect changes in physical activity (PA) measures (steps, “points,” kCals) in laboratory (LAB) and free-living (FL) conditions. Methods: Twenty-one participants wore the MS and ActiGraph GT3X+™ accelerometer (AG) at the hip and dominant-wrist during three, one-hour LAB sessions: sedentary (SS), sedentary plus walking (SW), and sedentary plus jogging (SJ). Direct observation (DO) of steps served as the criterion measure. Devices were also worn during two FL conditions: 1) active week (ACT) and 2) inactive week (INACT). For LAB and FL, significant differences were examined using paired t-tests and linear mixed effects models, respectively. Linear mixed effects models were used to estimate differences between MS estimated steps and DO (α ≤ 0.05). Results: For all hip-worn MS measures and wrist-worn MS estimates of steps and “points,” there was a significant increase (p < .05) from SS to SJ. However, wrist-worn MS kCal estimates were greater for SJ, compared to SS and SW, which were similar to each other (95% CI [95.5, 152.8] and [141.1, 378.9], respectively). Compared with DO, MS hip significantly underestimated steps by 3.5%, while MS wrist significantly overestimated steps by 4.2%. During FL conditions, all MS measures were sensitive to changes between ACT and INACT (p < .0001). Conclusion: Although there were systematic errors in step estimates from the MS, it was sensitive to changes during LAB and FL, and may be a useful tool for interventionists where tracking changes in PA is an important exposure or outcome variable.
Rachel Arnold, Nicole Bolter, Lori Dithurbide, Karl Erickson, Blair Evans, Larkin Lamarche, Sean Locke, Eric Martin and Kathleen Wilson
Edited by Kim Gammage
golfer’s confidence in his or her own abilities to determine yardage and how they trust technology impacts how they use a commonly used piece of technology in golf: distance measuring devices (DMDs; e.g., GPS, laser, range finder). Technology use in sport has significantly increased and will likely not
John M. Rosene, Christian Merritt, Nick R. Wirth and Daniel Nguyen
away games were not taken into consideration. The limited number of games that were monitored make the generalization to the lacrosse community difficult. However, other studies have reported similar head impact forces, albeit with different measuring devices. 11 – 13 Greater sample sizes over the