David O. Draper

Effects of warm-up before eccentric exercise on indirect markers of muscle damage.

PURPOSE To test whether active and passive warm-up conducted before eccentric exercise attenuates clinical markers of muscle damage. METHODS Untrained subjects were exposed to one of five conditions: low-heat passive warm-up (N = 10), high-heat passive warm-up (N = 4), or active warm-up (N = 9), preceding eccentric exercise; eccentric exercise without warm-up (N = 10); or high-heat passive warm-up without eccentric exercise (N = 10). Passive warm-up of the elbow flexors was achieved using pulsed short-wave diathermy, and active warm-up was achieved by concentric contraction. Creatine kinase (CK) activity, strength, range of motion, swelling, and muscle soreness were observed before treatment (baseline) and 24, 48, 72, and 168 h after treatment. RESULTS High-heat passive warm-up without eccentric exercise did not affect any marker of muscle damage and was used as our control group. Markers of muscle damage were not different between groups that did or did not conduct warm-up before eccentric exercise. The active warm-up and eccentric groups exhibited a greater circumferential increase than controls (P < 0.0002), however, that was not observed after passive warm-up. Additionally, the active warm-up group exhibited a greater CK response than controls at 72 h (P < 0.05). The high-heat passive warm-up before eccentric exercise group exhibited significant change from controls at the least number of time points, but due to a small sample size (N = 4), these data should be viewed as preliminary. CONCLUSION Our observations suggest that passive warm-up performed before eccentric exercise may be more beneficial than active warm-up or no warm-up in attenuating swelling but does not prevent, attenuate, or resolve more quickly the other clinical symptoms of eccentric muscle damage as produced in this study.

Thermal ultrasound decreases tissue stiffness of trigger points in upper trapezius muscles

ABSTRACT Many trigger point therapies, such as deep pressure massage and injection, are painful. Thermal ultrasound might be a comfortable procedure used to soften trigger points. Our objective was to compare thermal ultrasound with sham ultrasound in the ability to soften trigger points with pretest/posttest repeated-measures design for depth of tissue in a massage therapy clinic. Twenty-six patients with latent trigger points in their upper trapezius muscles were studied. Independent variables were treatments; dependent variables were tissue depth. Subjects were randomly assigned to either the treatment or sham group. The study was single-blinded; the investigator taking the measurements was blinded to which group the subjects were in, and the clinician treating with ultrasound was blinded to the measurements. Each trigger point in the treatment group received 3 MHz ultrasound at the following parameters: 1.4 W/cm2, 5 min, circular motion, 2× the size of the 7 cm2 soundhead. The ultrasound was not turned on for the sham group. This procedure was repeated one week later. Trigger point depth was measured with a pressure algometer before and immediately after each treatment. A 2×2×2 repeated measures ANOVA was used to analyze depth (mm). The immediate effects were as follows: The mean depth value for the sham group was an increase of 0.64±0.33 mm; the treatment groups mean increase was 2.65±0.33 mm (F1,24=19.01; p=0.01). The residual effects were as follows: The two treatments over the course of the 2 weeks also showed that the trigger points of the ultrasound groups got softer with an increase in depth of 2.09±0.82 mm compared to −0.93±0.82 mm of the sham group (F1,24=6.81; p<0.01). Thermal ultrasound over latent trigger points is comfortable and can decrease stiffness of a trigger point.

Whole-body vibration strengthening compared to traditional strengthening during physical therapy in individuals with total knee arthroplasty

ABSTRACT This study investigated the use of whole-body vibration (WBV) as an alternative strengthening regimen in the rehabilitation of individuals with total knee arthroplasty (TKA) compared with traditional progressive resistance exercise (TPRE). Individuals post TKA (WBV n = 8; TPRE n = 8) received physical therapy with WBV or with TPRE for 4 weeks. Primary dependent variables were knee extensor strength, quadriceps muscle activation, mobility, pain, and range of motion (ROM). There was a significant increase in knee extensor strength and improvements in mobility, as measured by maximal volitional isometric contraction and the Timed Up and Go Test (TUG), respectively, for both groups (p < 0.01). The WBV knee extensor strength improved 84.3% while TPRE increased 77.3%. TUG scores improved 31% in the WBV group and 32% for the TPRE group. There were no significant differences between groups for strength or muscle activation (Hotellings T2 = 0.42, p = 0.80) or for mobility (F = 0.54; p = 0.66). No adverse side effects were reported in either group. In individuals with TKA, both WBV and TPRE showed improved strength and function. Influence of WBV on muscle activation remains unclear, as muscle activation levels were near normal for both groups.

Reflex inhibition of electrically induced muscle cramps in hypohydrated humans.

INTRODUCTION Anecdotal evidence suggests that ingesting small volumes of pickle juice relieves muscle cramps within 35 s of ingestion. No experimental evidence exists supporting the ingestion of pickle juice as a treatment for skeletal muscle cramps. METHODS On two different days (1 wk apart), muscle cramps were induced in the flexor hallucis brevis (FHB) of hypohydrated male subjects (approximately 3% body weight loss and plasma osmolality approximately 295 mOsm x kg(-1) H2O) via percutaneous tibial nerve stimulation. Thirty minutes later, a second FHB muscle cramp was induced and was followed immediately by the ingestion of 1 mL x kg(-1) body weight of deionized water or pickle juice (73.9 +/- 2.8 mL). RESULTS Cramp duration and FHB EMG activity during the cramp were quantified, as well as the change in plasma constituents. Cramp duration (water = 151.9 +/- 12.9 s and pickle juice = 153.2 +/- 23.7 s) and FHB EMG activity (water = 60% +/- 6% and pickle juice = 68% +/- 9% of maximum voluntary isometric contraction EMG activity) were similar during the initial cramp induction without fluid ingestion (P > 0.05). During FHB muscle cramp induction combined with fluid ingestion, FHB EMG activity was again similar (water = 55% +/- 9% and pickle juice = 66% +/- 9% of maximum voluntary isometric contraction EMG activity, P > 0.05). However, cramp duration was 49.1 +/- 14.6 s shorter after pickle juice ingestion than water (84.6 +/- 18.5 vs 133.7 +/- 15.9 s, respectively, P < 0.05). The ingestion of water or pickle juice had little impact on plasma composition 5 min after ingestion. CONCLUSIONS Pickle juice, and not deionized water, inhibits electrically induced muscle cramps in hypohydrated humans. This effect could not be explained by rapid restoration of body fluids or electrolytes. We suspect that the rapid inhibition of the electrically induced cramps reflects a neurally mediated reflex that originates in the oropharyngeal region and acts to inhibit the firing of alpha motor neurons of the cramping muscle.

Absorption of iontophoresis-driven 2% lidocaine with epinephrine in the tissues at 5 mm below the surface of the skin.

CONTEXT In a recent study, we were unable to measure lidocaine in the human calf at a 5-mm depth via iontophoresis. We surmised that this might be due to a lack of epinephrine in the compound. Because epinephrine is a vasoconstrictor, it might allow the drug to pass beyond the capillaries and be delivered to the deeper tissues. OBJECTIVE To determine if iontophoresis could deliver lidocaine with epinephrine 5 mm under the surface of human skin, as measured by microdialysis. DESIGN Descriptive laboratory study. SETTING Therapeutic modalities research laboratory. PATIENTS OR OTHER PARTICIPANTS Ten volunteers (5 males, 5 females; age, 15-28 years) with less than 5 mm of adipose tissue in the area we measured and with no allergies to lidocaine participated. The measurement area had been free of any injury, swelling, or infection for at least 3 months before the study. INTERVENTION(S) We inserted a microdialysis probe 0.5 cm under the skin of the right lower leg. Next, microdialysis was performed through this area for 60 minutes, which allowed local skin blood flow to return to baseline. We then performed iontophoresis at 40 mA/min using 2 mL of 2% lidocaine. Iontophoresis was performed over this area for 10.5 minutes to collect the lidocaine samples. After this stage, the electrode was left in place for another 50 minutes for a total of 60 minutes. MAIN OUTCOME MEASURE(S) The samples of the drug were analyzed via reverse-phase high-performance liquid chromatography (RP-HPLC) in the chemistry department. RESULTS The RP-HPLC analysis confirmed the presence of lidocaine in all 10 participants. The mean concentration of lidocaine detected at the 5-mm depth was calculated as 3.63 mg/ mL (greater than 18% of delivered concentration). CONCLUSIONS We found that 2% lidocaine can be delivered up to 5 mm below the surface of the skin when the drug compound contains epinephrine and when passive delivery occurs for at least 50 minutes after the active delivery has terminated.

Temperature Increases in the Human Achilles Tendon During Ultrasound Treatments With Commercial Ultrasound Gel and Full-Thickness and Half-Thickness Gel Pads

CONTEXT Although originally manufactured for use in diagnostic imaging of internal structures, 2-cm-thick gel pads are also used as conducting media for therapeutic ultrasound over areas with bony prominences. Research on the ability of these pads to conduct enough energy to adequately heat tissues has provided mixed results. However, this research has mainly been performed on the triceps surae muscle, an area over which gel pads are not typically used. We wondered how much heating might be produced if a thinner pad was used over a tendon. OBJECTIVE To compare temperature rises in the human Achilles tendon during ultrasound treatments using ultrasound gel, a 2-cm-thick pad, and a 1-cm-thick pad. DESIGN Cross-sectional study. SETTING University therapeutic modality laboratory. PATIENTS OR OTHER PARTICIPANTS Forty-eight healthy volunteers (24 women, 24 men). INTERVENTION(S) We inserted a rigid thermocouple 1 cm deep into the Achilles tendon. Ultrasound was delivered at the following settings: 3 MHz, continuous, 1 W/cm(2), 10 minutes. MAIN OUTCOME MEASURE(S) Temperature was recorded every 30 seconds for 10 minutes. RESULTS Temperature increased the most in the ultrasound gel group (increase = 13.3 degrees C, peak = 42 degrees C). The 1-cm-thick pad resulted in higher tendon temperature (increase = 9.3 degrees C, peak = 37.8 degrees C) than the 2-cm-thick pad (increase = 6.5 degrees C, peak = 4.8 degrees C). The 1-cm pad produced approximately 30% more heating than the 2-cm pad (SE = 0.72, P < .03). CONCLUSIONS The thinner pad transmitted ultrasound more efficiently than the thicker pad. Thus, a gel pad of less than 1-cm thickness might be useful for superficial areas, such as the hands and ankles.

Don't Disregard Ultrasound Yet–The Jury Is Still Out

To the Editor: I am writing to provide my viewpoint on the article by Robertson and Baker titled “A Review of Therapeutic Ultrasound: Effectiveness Studies” (July 2001). I commend them on a very rigorous study. They reviewed 35 studies performed between 1975 and 1999, and then deleted 25 studies due to small sample size, nonclinical condition, and so forth. Of the 10 remaining studies, only 2 studies showed that active ultrasound performed better than placebo ultrasound. The authors drew the conclusion that active ultrasound is no more effective than placebo ultrasound. As I studied their report, I discovered flaws in the 8 studies from which they drew their conclusion. I base my opinion on a decade of laboratory research establishing correct ultrasound parameters.1–3 ### Effective Radiating Area Ultrasound crystals are not completely uniform, and some areas transmit sound better than others. The effective radiating area (ERA) is the amount of the crystal that transmits the sound wave. The crystal is housed inside the soundhead and is slightly smaller than the applicator faceplate.1–3 To obtain optimal ultrasound benefits, the treatment size should be no more than 2 times the size of the ERA of the crystal, or roughly twice the size of the soundhead. Only one of the studies deemed …

Ultrasound and Joint Mobilizations for Achieving Normal Wrist Range of Motion After Injury or Surgery: A Case Series

CONTEXT Regaining full, active range of motion (AROM) after trauma to the wrist is difficult. OBJECTIVE To report the cases of 6 patients who lacked full range of motion (ROM) in the wrist due to trauma. The treatment regimen was thermal 3-MHz ultrasound and joint mobilizations. DESIGN Case series. SETTING University therapeutic modalities laboratory. PATIENTS OR OTHER PARTICIPANTS Six patients (2 women, 4 men) from the university population lacked a mean AROM of 21.7° of flexion and 26.8° of extension approximately 2.1 years after trauma or surgery. MAIN OUTCOME MEASURE(S) I assessed changes in flexion and extension AROM before and after each treatment. Treatment consisted of 6 minutes of 3-MHz continuous ultrasound at an average intensity of 1.4 W/cm(2) on the dorsal and volar aspects of the wrist, immediately followed by approximately 10 minutes of joint mobilizations. After posttreatment ROM was recorded, ice was applied to the area for about 20 minutes. Once the patient achieved full AROM or did not improve on 2 consecutive visits, he or she was discharged from the study. RESULTS By the sixth treatment, 5 participants achieved normal flexion AROM, and 3 exceeded the norm. All 6 achieved normal extension AROM, and 4 exceeded the norm. All returned to normal activities and normal use of their hands. One month later, they had, on average, maintained 93% of their final measurements. CONCLUSIONS A combination of thermal ultrasound and joint mobilizations was effective in restoring AROM to wrists lacking ROM after injury or surgery.

Muscle Heating With Megapulse II Shortwave Diathermy and ReBound Diathermy

CONTEXT A new continuous diathermy called ReBound recently has been introduced. Its effectiveness as a heating modality is unknown. OBJECTIVE To compare the effects of the ReBound diathermy with an established deep-heating diathermy, the Megapulse II pulsed shortwave diathermy, on tissue temperature in the human triceps surae muscle. DESIGN Crossover study. SETTING University research laboratory. PATIENTS OR OTHER PARTICIPANTS Participants included 12 healthy, college-aged volunteers (4 men, 8 women; age = 22.2 ± 2.25 years, calf subcutaneous fat thickness = 7.2 ± 1.9 mm). INTERVENTION(S) Each modality treatment was applied to the triceps surae muscle group of each participant for 30 minutes. After 30 minutes, we removed the modality and recorded temperature decay for 20 minutes. MAIN OUTCOME MEASURE(S) We horizontally inserted an implantable thermocouple into the medial triceps surae muscle to measure intramuscular tissue temperature at 3 cm deep. We measured temperature every 5 minutes during the 30-minute treatment and each minute during the 20-minute temperature decay. RESULTS Tissue temperature at a depth of 3 cm increased more with Megapulse II than with ReBound diathermy over the course of the treatment (F₆,₆₆ = 10.78, P < .001). ReBound diathermy did not produce as much intramuscular heating, leading to a slower heat dissipation rate than the Megapulse II (F₂₀,₂₂₀ = 28.84, P < .001). CONCLUSIONS During a 30-minute treatment, the Megapulse II was more effective than ReBound diathermy at increasing deep, intramuscular tissue temperature of the triceps surae muscle group.

Effect of Patterned Electrical Neuromuscular Stimulation on Vertical Jump in Collegiate Athletes

Background: Patterned electrical neuromuscular stimulation (PENS) uses the electrical stimulation of sensory and motor nerves to achieve a skeletal muscle contraction using an electromyogram-derived functional pattern. PENS is used extensively for neuromuscular reeducation and treatment of muscle disuse atrophy. Purpose: To explore the effectiveness of PENS as applied to the quadriceps muscles on the vertical jump of an athletic population. Study Design: Experimental with control and repeated measures over time. Methods: Healthy college athletes (54 women, 75 men) were divided into 3 groups (control, n = 30; jump, n = 33; and jump with PENS, n = 63). There was no difference among groups’ height and weight. Athletes performed a baseline standing vertical jump using a vertical jump system. The control group continued its normal daily activities with no jumping tasks included. The jump groups performed 3 sets of 12 repetitions with a 2-minute rest between sets at a frequency of 3 times per week. The PENS group did the jumping with the coordination of an electrical stimulation system. Vertical jump was retested after 6 weeks of intervention and 2 weeks after cessation. Results: A 3-way repeated measures analysis of variance for time (control, jump alone, jump with PENS) revealed a significant difference (P < 0.05) for time and an interaction between time and treatment, as well as a significant difference for the PENS group from baseline to posttest and for the jump group from posttest to follow-up jump. There was no significant difference between groups for the baseline vertical jump. Conclusions: This study demonstrated that 6 weeks of vertical jump training coordinated with PENS resulted in a greater increase than jumping only or control. This pattern of stimulation with PENS in combination with jump training may positively affect jumping.