We propose that physiological and performance tests used in sport science research and professional practice should be developed following a rigorous validation process, as is done in other scientific fields, such as clinimetrics, an area of research that focuses on the quality of clinical measurement and uses methods derived from psychometrics. In this commentary, we briefly review some of the attributes that must be explored when validating a test: the conceptual model, validity, reliability, and responsiveness. Examples from the sport science literature are provided.
Franco M. Impellizzeri and Samuele M. Marcora
Costas A. Anastasiou, Stavros A. Kavouras, Christina Koutsari, Charalambos Georgakakis, Katerina Skenderi, Michael Beer and Labros S. Sidossis
This study examined the effect of maltose-containing sports drinks on exercise performance. Ten subjects completed 4 trials. Each trial consisted of a glycogen depletion protocol, followed by a 15-min refueling, after which subjects performed an 1-h performance test while consuming one of the experimental drinks (HGlu, glucose; HMal, maltose; MalMix, sucrose, maltose, and maltodextrin; Plac, placebo). Drinks provided 0.65 g/kg body weight carbohydrates during refueling and 0.2 g/kg every 15 min during the performance test. Although no significant differences were found in performance (HGlu: 67.2 ± 2.0; HMal: 68.6 ± 1.7; MalMix: 66.7 ± 2.0; Plac: 69.4 ± 3.0 min, P > 0.05), subjects completed the MalMix trial 3.9% faster than the Plac. Carbohydrate drinks caused comparable plasma glucose values that were significantly higher during refueling and at the end of exercise, compared to Plac. The data suggest that although carbohydrate drinks help to maintain plasma glucose at a higher level, no differences in performance could be detected after glycogen-depleting exercise.
Chris R. Abbiss, Paolo Menaspà, Vincent Villerius and David T. Martin
A number of laboratory-based performance tests have been designed to mimic the dynamic and stochastic nature of road cycling. However, the distribution of power output and thus physical demands of high-intensity surges performed to establish a breakaway during actual competitive road cycling are unclear. Review of data from professional road-cycling events has indicated that numerous short-duration (5–15 s), high-intensity (~9.5–14 W/kg) surges are typically observed in the 5–10 min before athletes’ establishing a breakaway (ie, riding away from a group of cyclists). After this initial high-intensity effort, power output declined but remained high (~450–500 W) for a further 30 s to 5 min, depending on race dynamics (ie, the response of the chase group). Due to the significant influence competitors have on pacing strategies, it is difficult for laboratory-based performance tests to precisely replicate this aspect of mass-start competitive road cycling. Further research examining the distribution of power output during competitive road racing is needed to refine laboratory-based simulated stochastic performance trials and better understand the factors important to the success of a breakaway.
Nai-Hsin Meng, Chia-Ing Li, Chiu-Shong Liu, Wen-Yuan Lin, Chih-Hsueh Lin, Chin-Kai Chang, Tsai-Chung Li and Cheng-Chieh Lin
To compare muscle strength and physical performance among subjects with and without sarcopenia of different definitions.
A population-based cross-sectional study.
857 community residents aged 65 years or older.
Sarcopenia was defined according to the European Working Group of Sarcopenia in Older People consensus criteria. Dual-energy X-ray absorptiometry measured lean soft tissue mass. Sarcopenic participants with low height-adjusted or weight-adjusted skeletal muscle index (SMI) were classified as having h-sarcopenia or w-sarcopenia, respectively. Combined sarcopenia (c-sarcopenia) was defined as having either h- or w-sarcopenia. The participants underwent six physical performance tests: walking speed, timed up-and-go, six-minute walk, single-leg stance, timed chair stands, and flexibility test. The strength of five muscle groups was measured.
Participants with h-sarcopenia had lower weight, body mass index (BMI), fat mass, and absolute muscle strength (p ≤ .001); those with w-sarcopenia had higher weight, BMI, fat mass (p < .001), and low relative muscle strength (p ≤ .003). Participants with c-sarcopenia had poorer performance in all physical performance tests, whereas h-sarcopenia and w-sarcopenia were associated with poor performance in four tests.
Subjects with h- and w-sarcopenia differ significantly in terms of obesity indicators. Combining height- and weight-adjusted SMIs can be a feasible method to define sarcopenia.
Martin Aedma, Saima Timpmann and Vahur Ööpik
Peak power (PP) and mean power (MP) attained in upper body sprint performance test are considered important factors for competitive success in wrestling. This study aimed to determine whether acute caffeine ingestion would better maintain PP and MP across a simulated competition day in wrestling.
In a double-blind, counterbalanced, crossover study, 14 trained wrestlers ingested either placebo or 5 mg/kg caffeine and completed four 6-min upper body intermittent sprint performance tests with 30-min recovery periods between consecutive tests. PP and MP were recorded during and blood lactate concentration was measured before and after each test. Ratings of perceived fatigue (RPF) and exertion (RPE) were recorded before and after each test, respectively. Heart rate (HR) was monitored across the whole testing period.
Mean power decreased across four tests in both trials (p < .05), but the reduction in PP (from 277.2 ± 34.6 W to 257.3 ± 45.1 W; p < .05) only occurred in caffeine trial. Both pretest blood lactate concentration and HR were higher in caffeine than in placebo trial (p < .05) in the third and fourth tests. No between-trial differences occurred in RPF or RPE.
Under simulated competition day conditions mimicking four consecutive wrestling matches, acute caffeine ingestion has a partially detrimental effect on upper body intermittent sprint performance in trained wrestlers. Elevated HR and blood lactate levels observed between tests after caffeine ingestion suggest that caffeine may impair recovery between consecutive maximal efforts.
Owen Spendiff and Ian G. Campbell
Seven athletes with low lesion paraplegia ingested a 7.6% 648ml glucose drink using two schedules of ingestion (4 × 162 ml per 20 min & 2 × 324 ml per 60 min) in a crossover design. Participants exercised at 65% peak oxygen uptake for one hour, followed by a 20-minute performance test. The cardiorespiratory responses during the one-hour tests were similar between trials. Plasma glucose concentrations significantly increased after ingestion and remained stable during the 162 trial, but reduced over time during the 324 trial. Free fatty acid concentrations increased for both trials but increased significantly more during the 324 trial. The results of this study suggest that the ingestion of glucose during exercise is the best strategy for wheelchair athletes competing in endurance events.
Suzanne C. Hoeppner and James H. Rimmer
The purpose of this study was to determine if self-reported exercise status (exercise, nonexercise) and ambulatory status (aid, no aid) discriminate between balance performance and balance self-efficacy of older adults, ages 65 to 95 years. Participants were 14 males and 46 females in a retirement home that contained a supervised fitness center. An activities-specific balance confidence scale and three balance performance tests yielded data. Data from males and females were combined because independent t tests revealed no significant gender differences. The Mann Whitney U test revealed that (a) exercisers (M age = 83.4) scored significantly higher than nonexercisers (M age = 83.7) on all measures, and (b) nonaid users (M age = 83.5) scored significantly higher than aid users (M age = 83.7). Findings indicate that regular exercise (at least 30 min per day, 3 days per week) and ambulation without a cane or walker are descriptors of older adults with good balance performance and high balance self-efficacy.
Lori A. Bolgla, Douglas R. Keskula and Jewell B. Duncan
Researchers have suggested that quadriceps inhibition resulting from a simulated knee effusion would lead to decreased lower extremity performance.
To investigate the relationship between a simulated knee effusion and lower extremity performance.
9 college students.
Subjects performed 3 functional-performance tests before and after a simulated knee effusion. Measurement was the average distance hopped for a single hop and crossover hop for distance and time for completion on a timed hop test.
An analysis of variance revealed significant change in average test scores after injection only for the timed hop in subjects receiving a 60-ml injection.
Nonsignificant differences might have resulted from compensation from other muscle groups, fluid movement within the knee joint, and absence of an inflammatory process. Further research on the relationship between simulated knee effusion and lower extremity performance is needed.
Michael A. Tabor, George J. Davies, Thomas W. Kernozek, Rodney J. Negrete and Vincent Hudson
Many clinicians use functional-performance tests to determine an athlete’s readiness to resume activity; however, research demonstrating reliability of these tests is limited.
To introduce the Lower Extremity Functional Test (LEFT) and establish it as a reliable assessment tool.
Week 1: Subjects participated in a training session. Week 2: Initial maximal-effort time measurements were recorded. Week 3: Retest time measurements were recorded.
The University of Wisconsin–La Crosse (UW-L) and the University of Central Florida (UCF).
27 subjects from UW-L and 30 from UCF.
Main Outcome Measures:
Time measurements were analyzed using intraclass correlation coefficients (ICCs).
ICC values of .95 and .97 were established at UW-L and UCF, respectively.
The LEFT is a reliable assessment tool.
B. Josea Kramer, Beth Creekmur, Michael N. Mitchell, Debra J. Rose, Jon Pynoos and Laurence Z. Rubenstein
The Fall Prevention Center of Excellence designed three progressive-intensity fall prevention program models, Increasing Stability Through Evaluation and Practice (InSTEP), to reduce risk in community-dwelling older adults. Each model included physical activity, medical risk, and home safety components and was implemented as a 12-week program for small class sizes (12–15 people) in community and senior centers. Change in fall rates and fall risk factors was assessed using a battery of performance tests, self-reports of function, and fall diaries in a 3-group within-subjects (N = 200) design measured at baseline, immediately postintervention, and at 3 and 9 months postintervention. Overall, participants experienced a reduction in falls, improved self-perception of gait and balance, and improved dynamic gait function. The medium-intensity InSTEP model signifcantly (p = .003) reduced self-reported falls in comparison with the other models. InSTEP is a feasible model for addressing fall risk reduction in community-dwelling older adults.