An 18-day stretching regimen, with or without pulsed, shortwave diathermy, and ankle dorsiflexion after 3 weeks.

CONTEXT: The amount of retained ankle flexibility gains and the effects of diathermy on those gains are unclear.

OBJECTIVE: To determine the retention of flexibility 3 weeks after an 18-day stretching regime and the effect of pulsed, shortwave diathermy on that retention.

DESIGN: We used a 2x4 factorial with repeated measures on day (1, 19, 24, and 39). The other independent variable was treatment (stretch only versus diathermy and stretch). The dependent variable was ankle-dorsiflexion angular displacement as measured on a digital inclinometer.

SETTING: Therapeutic Modality Research Laboratory.

PATIENTS OR OTHER PARTICIPANTS: 23 healthy college-aged volunteers (8 males, 15 females; age = 22.7 +/- 2.1 years, height = 171.1 +/- 8.8 cm, mass = 70.4 +/- 13.5 kg).

INTERVENTIONS: All subjects performed 3 weeks (not including weekends) of low-load, prolonged, long-duration stretching. One group performed stretching only; the other group also received diathermy.

MAIN OUTCOME MEASURE(S): After an 18-day stretching regime and 7-day retention study, subjects returned 14 days later for the 3-week retention measure. The angle of inclination from the posterior Achilles tendon to the sole of the shoe near the heel was measured on each treatment and test day.

RESULTS: Regardless of group (F(1,21) = 0.74, P = 0.40), the flexibility gained between days 1 (99.7 +/- 4.0 degrees), 19 (102.9 +/- 5.8 degrees), and 24 (105.0 +/- 6.2 degrees) were maintained at day 39 (104.8+/- 7.2 degrees) (P < .05).

CONCLUSIONS: Flexibility gains in normal ankles with 3 weeks of training were retained for at least 3 weeks after training ceased. The application of pulsed, shortwave diathermy during stretching did not appear to influence the chronic retention of flexibility gains in normal subjects.