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Effectiveness of Clinical Ultrasound Parameters on Changing Intramuscular Temperature

Timothy J. Demchak and Marcus B. Stone

Context:

Researchers have recommended certain ultrasound treatment parameters for deep heating; however, we observed different parameters in the clinical setting.

Objective:

To compare the treatment effect of using observed clinical parameters (OCP) from 8 clinicians to the treatment effect of using the recommended parameters (RP) sited in research.

Design:

2 × 2 repeated measures design.

Setting:

Sports injury research laboratory.

Participants:

Ten healthy volunteers.

Interventions:

Two 1 MHz treatment, 1 RP treatment (1.5 W/cm2, 10-min, area-2 to 3 × ERA), and 1 OCP treatment (1.3 W/cm2, 8-min, area 3.9 × ERA)

Main Outcome Measure:

Tricep surae temperature 3 cm below superficial tissue

Results:

The RP treatment increase temperature from 36.4 ± 1.0 to 40.3± 2.0°C, which was a greater change than the OCP (36.5 ± 1.2 to 38.2 ± 1.6°C).

Conclusions:

The OCP treatment resulted in a lower heating affect than the RP. Small change in treatment area, intensity, and duration can have a large effect on temperature change.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 17 (2008): Issue 3 (Jan 2008)

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Ultrasound Heating Is Curvilinear in Nature and Varies between Transducers from the Same Manufacturer

Timothy J. Demchak, Stephen J. Straub, and Lennart D. Johns

Context:

Ultrasound heating rates are known to differ between various manufacturers; it is unknown whether this difference exists within a manufacturer.

Objective:

Determine if intramuscular heating differences exist between transducers from the same manufacturer.

Study Design:

3 × 10 repeated measures. Independent variables were Transducer (A, B, and C) and Time (10-min time points during the treatment).

Setting:

Controlled laboratory.

Participants:

Twelve volunteers (M = 4, F = 8; age: 23 ± 4 years; calf-girth: 37.94 ± 4.16 cm; calf-skinfold: 27 ± 17 mm).

Intervention:

Three 10-min 1MHz continuous ultrasound treatments performed at an intensity of 1.2 W/cm2, over an area 2x transducer.

Main Outcome Measures:

Calf temperature increase.

Results:

Heating curve generated for each transducer were significantly different (P = .034) but the overall temperature increases following 10 minutes of treatment were within 0.1°C (F = 1.023 P = .573).

Conclusion:

Heating curves differ between transducers from the same manufacturer but peak heating at 10 minutes was similar.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 16 (2007): Issue 2 (Jan 2007)

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Effects of Altering Intensity during 1-MHz Ultrasound Treatment on Increasing Triceps Surae Temperature

Phillip O. Burr, Timothy J. Demchak, Mitchell L. Cordova, Christopher D. Ingersoll, and Marcus B. Stone

Context:

It has been suggested that to obtain optimal physiological effects of heating, musculoskeletal temperature (TEMP) should be elevated 3 °C above baseline and maintained for at least 5 min.

Objective:

To identify a multi-intensity ultrasound protocol that will achieve optimal heating.

Design:

1 × 2 between-subjects.

Setting:

Sports-injury research laboratory.

Participants:

20 healthy volunteers.

Interventions:

A 2.5-min treatment at 2.4 W/cm2 immediately followed by a 7.5-min treatment at 1.0 W/cm2 (T1) and a 10-min treatment at 1.5 W/cm2 (T2).

Outcome Measures:

TEMP change during the first 2.5 min of ultrasound treatment (°C), time the TEMP was ≥3 °C above baseline during and after the treatment.

Results:

T1 increased TEMP during the first 2.5 min of the ultrasound treatment (3.22 ± 1.25 °C) more than T2 did (1.68 ± 0.72 °C). No difference was found for the remaining measures.

Conclusions:

The multi-intensity protocol (2.4 W/cm2 and 1.0 W/cm2) did not result in optimal heating.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 13 (2004): Issue 4 (Jan 2004)

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The Effects of Walking on Gastrocnemius Cooling During an Ice Bag Treatment

Stephanie J. Guzzo, Susan W. Yeargin, Jeffery S. Carr, Timothy J. Demchak, and Jeffrey E. Edwards

Context:

Many athletic trainers use “ice to go” to treat their athletes. However, researchers have reported that icing a working muscle may negate intramuscular (IM) cooling.

Objective:

The purpose of our study was to determine the length of time needed to cool the gastrocnemius while walking followed by rest.

Design:

A randomized crossover study design was used.

Setting:

Exercise Physiology Laboratory.

Patients or Other Participants:

Nine healthy, physically active males and females (males 5, females 4; age 24.0 ± 2.0 years; height 174.0 ± 8.0 cm; weight 86.3 ± 6.5 kg; skinfold taken at center of gastrocnemius greatest girth, R leg 20.3 ± 4.4 mm, L leg 19.6 ± 4.1 mm) without lower extremity injury or cold allergy volunteered to complete the study.

Intervention:

Participants randomly experienced three treatment conditions on separate days: rest (R), walk for 15 minutes followed by rest (W15R), or walk for 30 minutes followed by rest (W30R). During each treatment, participants wore a 1 kg ice bag secured to their right gastrocnemius muscle. Participants walked at a 4.5km/hr pace on a treadmill during the W15R and W30R trials.

Main Outcome Measures:

A 1 × 3 within groups ANOVA was used to determine the effect of activity on cooling time needed for the gastrocnemius temperature to decrease 6 °C below baseline.

Results:

The R condition cooled faster (25.9 ± 5.5 min) than both W15R (33.7 ± 9.3 min; P = .002) and W30R (49.4 ± 8.4 min; P < .001). Average time to decrease 6 °C after W15R was 18.7 ± 9.3 minutes and after W30R was 19.4 ± 8.4 minutes.

Conclusions:

Clinicians should instruct their patients to stay and ice or to keep the ice on for an additional 20 minutes after they stop walking and begin to rest.

Cover International Journal of Athletic Therapy and Training

In International Journal of Athletic Therapy and Training Volume 19 (2014): Issue 6 (Nov 2014)