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  • Author: Timothy Demchak x
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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.

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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.

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Lindsey E. Eberman, Jesse Moore and Timothy Demchak

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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.

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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.

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Ai Ujino, Lindsey E. Eberman, Leamor Kahanov, Chelsea Renner and Timothy Demchak