Kathleen S. Thomas

Real-Time Intersession and Interrater Reliability of the Functional Movement Screen

Onate, JA, Dewey, T, Kollock, RO, Thomas, KS, Van Lunen, BL, DeMaio, M, and Ringleb, SI. Real-time intersession and interrater reliability of the functional movement screen. J Strength Cond Res 26(2): 408–415, 2012—The purpose of this study was to examine the real-time intersession and interrater reliability of the functional movement screen (FMS). The overall study consisted of 19 volunteer civilians (12 male, 7 female). The intersession reliability consisted of 12 men and 7 women, whereas 10 men and 6 women participated in the interrater reliability test session. Two raters (A and B) were involved in the interrater reliability aspect of this study. The FMS includes 7 tests: deep squat (DS), hurdle step (HS), in-line lunge (IL), shoulder mobility (SM), active straight leg raise (ASLR), trunk stability push-up (TSPU), and rotary stability (RS). Researchers analyzed the data via intraclass correlation (ICC). To determine the reliability of the intersession scoring of the FMS and the intrasession interrater scoring of the FMS a 2-way mixed effects model intraclass correlation coefficient (ICC3,1) was used for the continuous data, whereas a weighted Cohens kappa (κ) was used for the categorical data. The dependent variables were FMS total score (0–21 scale) and associated tests were DS, HS, IL, SM, ASLR, TSPU, and RS. Intersession reliability (ICC, SEM) and κ were as follows: FMS total score (0.92, 0.51), DS (κ = 0.69), HS (κ = 0.16), IL (κ = 0.69), SM (κ = 0.84), ASLR (κ = 0.69), TSPU (κ = 0.77), and RS (no covariance). Interrater reliability (ICC, SEM) and κ were as follows: FMS total score (0.98, 0.25), DS (κ = 1.0), HS (κ = 0.33), IL (κ = 0.88), SM (κ = 0.90), ASLR (κ = 0.88), TSPU (κ = 0.75), and RS (no covariance). The FMS total scores displayed high intersession and interrater reliabilities. Finally, with the exception of HS, all tasks displayed moderate to high intersession reliability and good to high interrater reliability.

The impact of speed and time on gait dynamics

To determine the effects of speed on gait previous studies have examined young adults walking at different speeds; however, the small number of strides may have influenced the results. The aim of this study was to investigate the immediate and long-term impact of continuous slow walking on the mean, variability and structure of stride-to-stride measures. Fourteen young adults walked at a constant pace on a treadmill at three speeds (preferred walking speed (PWS), 90% and 80% PWS) for 30 min each. Spatiotemporal gait parameters were computed over six successive 5-min intervals. Walking slower significantly decreased stride length, while stride period and width increased. Additionally, stride period and width variability increased. Signal regularity of stride width increased and decreased in stride period. Persistence of stride period and width increased significantly at slower speeds. While several measures changed during 30min of walking, only stride period variability and signal regularity revealed a significant speed and time interaction. Healthy young adults walking at slower than preferred speeds demonstrated greater persistence and signal regularity of stride period while spatiotemporal changes such as increased stride width and period variability arose. These results suggest that different control processes are involved in adapting to the slower speeds.

Aerobic training increases skin perfusion by a nitric oxide mechanism in type 2 diabetes

It is well known that a number of locally released vasodilatory and vasoconstrictive compounds can affect skin perfusion. This study investigated the effects of aerobic training on the contribution of nitric oxide (NO), prostaglandins (PG), and endothelial-derived hyperpolarizing factor (EDHF) in stimulated dorsal foot skin perfusion in individuals with type 2 diabetes (T2DM). Ten previously sedentary, older individuals with T2DM (57.0 ± 3.1 years) and nine sedentary controls (53.5 ± 3.2 years) were tested before and after undertaking six months of moderate aerobic training three times weekly in a supervised setting. All subjects underwent measurement of baseline (32°C) and heat-stimulated (40°C and 44°C) dorsal foot skin perfusion starting one hour after ingestion of a single, oral 325 mg dose of aspirin, a known inhibitor of PG synthesis. Before aspirin ingestion, a subcutaneous microdialysis probe was inserted into each foot dorsum to administer either saline (PG pathway only blocked by aspirin in the left foot) or L-NAME (N(G)-nitro-l-arginine methyl ester; thereby inhibiting both PG and NO pathways in the right foot). Normative data collected previously on subjects undergoing saline administration via microdialysis without aspirin ingestion served as a control group. Significantly lower responsiveness of maximal perfusion was found with the EDHF pathway alone unblocked compared with NO and EDHF unblocked after training. Maximal suppression attributable directly to NO, PG, and EDHF was not significantly different when examined by subject group and training status. However, contributions of NO, PG, and EDHF to maximal perfusion were significantly increased, decreased, and unchanged by aerobic training, respectively, with diabetic and control subjects combined due to nonsignificant differences between groups. Improvements in maximally stimulated dorsal foot skin perfusion resulting from six months of aerobic training appear to have primarily an NO basis, with lesser contributions from PG following training, regardless of diabetes status.

How does physical activity impact postural stability

Physical activity has been associated with an overall improvement in health by reducing disease and assisting in weight management. However, varying levels of physical activity has been shown to have immediate adverse effects on measures of postural stability. Increases in postural sway occur as a result of performing fatiguing exercise to specific muscles in addition to moderate to maximal intensity exercise. While this is often not problematic for healthy young adults this could produce challenges to individuals with balance impairments and older adults. This review investigates the immediate impact that various physical activity levels have on postural stability. In addition, the areas that require further investigation will be highlighted.

Graded forward and backward walking at a matched intensity on cardiorespiratory responses and postural control

BACKGROUND While several studies compare backward walking (BW) and forward walking (FW) in terms of heart rate (HR) and rating of perceived exertion (RPE), workload (VO2) was not matched to control for intensity levels (Hooper et al. [1]). Moreover, acute effects of inclined BW on postural control and ankle musculature has not been investigated. This study was designed to compare cardiovascular, metabolic and perceptual responses, changes in center of pressure (COP) motion, and muscle activation of tibialis anterior (TA) and gastrocnemius (GM) to control quiet stance posture immediately following inclined BW and FW at a matched intensity. METHODS Seventeen healthy young adults completed three lab sessions 7-14 days apart. Session one, maximal oxygen consumption (VO2max) was measured using open-circuit spirometry for each participant. Session two, participants performed BW for 15-min. Session three, participants performed FW for 15-min at matched intensity of BW. Surface electromyography (SEMG) measured the muscular activity of the TA and GM during bilateral stance on a force plate for 30 s prior to and immediately following BW and FW under both eyes open (EO), and eyes closed (EC) conditions. RESULTS HR, VCO2, RER and RPE were significantly greater during BW compared to FW. Increased muscle activation and COP motion was elicited immediately following BW compared to FW under EO and EC. CONCLUSION Results of this study indicate BW requires greater cardiovascular, metabolic, perceptual and neuromuscular demands than FW, which may cause postural instability particularly to those with compromised balance. While there are benefits to BW in rehabilitation settings, these factors should be considered when prescribing BW for training and/or rehabilitation exercise program (Duffell et al. [2], Warnica et al. [3]).BACKGROUND While several studies compare backward walking (BW) and forward walking (FW) in terms of heart rate (HR) and rating of perceived exertion (RPE), workload (VO2) was not matched to control for intensity levels (Hooper et al. [1]). Moreover, acute effects of inclined BW on postural control and ankle musculature has not been investigated. This study was designed to compare cardiovascular, metabolic and perceptual responses, changes in center of pressure (COP) motion, and muscle activation of tibialis anterior (TA) and gastrocnemius (GM) to control quiet stance posture immediately following inclined BW and FW at a matched intensity. METHODS Seventeen healthy young adults completed three lab sessions 7-14 days apart. Session one, maximal oxygen consumption (VO2max) was measured using open-circuit spirometry for each participant. Session two, participants performed BW for 15-min. Session three, participants performed FW for 15-min at matched intensity of BW. Surface electromyography (SEMG) measured the muscular activity of the TA and GM during bilateral stance on a force plate for 30 s prior to and immediately following BW and FW under both eyes open (EO), and eyes closed (EC) conditions. RESULTS HR, VCO2, RER and RPE were significantly greater during BW compared to FW. Increased muscle activation and COP motion was elicited immediately following BW compared to FW under EO and EC. CONCLUSION Results of this study indicate BW requires greater cardiovascular, metabolic, perceptual and neuromuscular demands than FW, which may cause postural instability particularly to those with compromised balance. While there are benefits to BW in rehabilitation settings, these factors should be considered when prescribing BW for training and/or rehabilitation exercise program (Duffell et al. [2], Warnica et al. [3]).