Ankle dorsiflexion range of motion influences Lateral Step Down Test scores in individuals with chronic ankle instability.

OBJECTIVES: To determine differences in ankle dorsiflexion range of motion (ROM) between three groups of individuals with chronic ankle instability (CAI) based on Lateral Step Down Test quality of movement. The secondary purpose was to quantify the relationship between ankle dorsiflexion ROM and Lateral Step Down Test scores. DESIGN: Descriptive laboratory study. SETTING: University research laboratory. PARTICIPANTS: Fifty-nine participants with CAI. MAIN OUTCOME MEASURES: Differences in ankle dorsiflexion ROM between three Lateral Step Down Test movement quality groups (good, moderate, poor) was determined using an analysis of variance. The relationship between outcome variables was determined using a Spearman rank correlation coefficient. RESULTS: Significantly less ankle dorsiflexion ROM was observed in individuals with poor movement quality (36.0 ± 6.6°) compared to good (42.3 ± 6.4°). Individuals with moderate movement quality did not have ankle dorsiflexion ROM (39.1 ± 6.2°) that was significantly different from either group. There was a negative correlation (r = -0.39) between ankle dorsiflexion ROM and Lateral Step Down Test scores. CONCLUSIONS: Participants in the poor movement quality group had 6° less ankle dorsiflexion ROM than participants in the good movement quality group. While ankle dorsiflexion ROM is associated with Lateral Step Down Test scores additional factors likely contribute to movement dysfunction in individuals with CAI. TRIAL REGISTRY: This trial was registered on ClinicalTrials.gov (NCT01438905).

Resistance training vs. static stretching: effects on flexibility and strength.

Morton, SK, Whitehead, JR, Brinkert, RH, and Caine, DJ. Resistance training vs. static stretching: Effects on flexibility and strength. J Strength Cond Res 25(12): 3391-3398, 2011-The purpose of this study was to determine how full-range resistance training (RT) affected flexibility and strength compared to static stretching (SS) of the same muscle-joint complexes in untrained adults. Volunteers (n = 25) were randomized to an RT or SS training group. A group of inactive volunteers (n = 12) served as a convenience control group (CON). After pretesting hamstring extension, hip flexion and extension, shoulder extension flexibility, and peak torque of quadriceps and hamstring muscles, subjects completed 5-week SS or RT treatments in which the aim was to stretch or to strength train the same muscle-joint complexes over similar movements and ranges. Posttests of flexibility and strength were then conducted. There was no difference in hamstring flexibility, hip flexion, and hip extension improvement between RT and SS, but both were superior to CON values. There were no differences between groups on shoulder extension flexibility. The RT group was superior to the CON in knee extension peak torque, but there were no differences between groups on knee flexion peak torque. The results of this preliminary study suggest that carefully constructed full-range RT regimens can improve flexibility as well as the typical SS regimens employed in conditioning programs. Because of the potential practical significance of these results to strength and conditioning programs, further studies using true experimental designs, larger sample sizes, and longer training durations should be conducted with the aim of confirming or disproving these results.