STUDY DESIGN: A repeated-measure crossover design was used. The independent variable was the type of ultrasound (pulsed or continuous) and the dependent variable was intramuscular temperature. OBJECTIVE: To compare changes in intramuscular temperature resulting from the use of pulsed ultrasound versus continuous ultrasound with an equivalent spatial average temporal average (SATA) intensity. BACKGROUND: There is a lack of research on the heat-generating capabilities of pulsed ultrasound within human muscle. METHODS AND MEASURES: The subjects were 16 healthy volunteers (mean age +/- SD, 21.3 +/- 2.5 years). Each subject was treated with pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) and continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) during a single testing session. Tissue temperature returned to baseline and stabilized between treatments and treatment order was randomized. Tissue temperature was measured every 30 seconds using a 26-gauge needle microprobe inserted at a depth of 2 cm in the left medial gastrocnemius muscle. Data were analyzed using a linear mixed model. RESULTS: Treatment with continuous ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.8 degrees C above baseline. Treatment with pulsed ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.7 degrees C above baseline. Statistical analysis revealed no significant differences in either the extent or rate of temperature increases between the 2 modes of ultrasound application. CONCLUSION:Pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) produces similar intramuscular temperature increases as continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) at a 2-cm depth in the human gastrocnemius. Spatial average temporal average intensity is an important consideration when selecting pulsed ultrasound parameters intended to deliver nonthermal effects.
RCT Entities:
STUDY DESIGN: A repeated-measure crossover design was used. The independent variable was the type of ultrasound (pulsed or continuous) and the dependent variable was intramuscular temperature. OBJECTIVE: To compare changes in intramuscular temperature resulting from the use of pulsed ultrasound versus continuous ultrasound with an equivalent spatial average temporal average (SATA) intensity. BACKGROUND: There is a lack of research on the heat-generating capabilities of pulsed ultrasound within human muscle. METHODS AND MEASURES: The subjects were 16 healthy volunteers (mean age +/- SD, 21.3 +/- 2.5 years). Each subject was treated with pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) and continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) during a single testing session. Tissue temperature returned to baseline and stabilized between treatments and treatment order was randomized. Tissue temperature was measured every 30 seconds using a 26-gauge needle microprobe inserted at a depth of 2 cm in the left medial gastrocnemius muscle. Data were analyzed using a linear mixed model. RESULTS: Treatment with continuous ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.8 degrees C above baseline. Treatment with pulsed ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.7 degrees C above baseline. Statistical analysis revealed no significant differences in either the extent or rate of temperature increases between the 2 modes of ultrasound application. CONCLUSION: Pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) produces similar intramuscular temperature increases as continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) at a 2-cm depth in the human gastrocnemius. Spatial average temporal average intensity is an important consideration when selecting pulsed ultrasound parameters intended to deliver nonthermal effects.
Authors: Lisa S Jutte; Kenneth L Knight; Blaine C Long; Jeremy R Hawkins; Shane S Schulthies; Ethan B Dalley Journal: J Athl Train Date: 2005 Jul-Sep Impact factor: 2.860
Authors: Michale G Miller; Janae R Longoria; Christopher C Cheatham; Robert J Baker; Timothy J Michael Journal: J Sports Sci Med Date: 2008-06-01 Impact factor: 2.988
Authors: Wouber Herickson de Brito Vieira; Kardec Alecxandro Aguiar; Kimberly Moreira da Silva; Pablo Miranda Canela; Flávio Santos da Silva; Bento João Abreu Journal: Crit Ultrasound J Date: 2012-05-28