Influence of Compression Therapy on Symptoms Following Soft Tissue Injury from Maximal Eccentric Exercise

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1 Journal of Orthopaedic & Sports Physical Therapy 2001 ;31(6): Influence of Compression Therapy on Symptoms Following Soft Tissue Injury from Maximal Eccentric Exercise William ). Kraemer, PhD )ill A. Bush, PhD2 Robbin B. Wickham, MSPT1 Craig R. Denegar, PhD, PT2 Ana I. Gbmez, MS1 Lincoln A. Gotshalk, PhD2 Noel D. Duncan, PhD2 /eff S. Volek, PhD, RD Margot Putukian, MD2 Wayne ). Sebastianelli, MD2 Study Design: A between groups design was used to compare recovery following eccentric muscle damage under 2 experimental conditions. Objectiw To determine if a compression sleeve donned immediately after maximal eccentric exercise would enhance recovery of physical function and decrease symptoms of soreness. Background: Prior investigations using ice, intermittent compression, or exercise have not shown efficacy in relieving symptoms of delayed onset muscle soreness (DOMS). To date, no study has shown the effect of continuous compression on DOMS, yet this would offer a low cost intervention for patients suffering with the symptoms of DOMS. Methods and Measures: Twenty nonimpaired non-strength-trained women participated in the study. Subjects were matched for age, anthropometric data, and one repetition maximum concentric arm curl strength and then randomly placed into a control group (n = 10) or an experimental compression sleeve group (n = 10). Subjects were instructed to avoid pain-relieving modalities (eg, analgesic medications, ice) throughout the study. The experimental group wore a compressive sleeve garment for 5 days following eccentric exercise. Subjects performed 2 sets of 50 passive arm curls with the dominant arm on an isokinetic dynamometer with a maximal eccentric muscle action superimposed every fourth passive repetition. One repetition maximum elbow flexion, upper arm circumference, relaxed elbow angle, blood serum cortisol, creatine kinase, lactate dehydrogenase, and perception of soreness questionnaires were collected prior to the exercise bout and daily thereafter for 5 days. Results: Creatine kinase was significantly elevated from the baseline value in both groups, although the experimental compression test group showed decreased magnitude of creatine kinase elevation following the eccentric exercise. Compression sleeve use prevented loss of elbow motion, decreased perceived soreness, reduced swelling, and promoted recovery of force production. Conclusiom: Results from this study underline the importance of compression in soft tissue injury management. ) Orthop Sports Phys Ther 2001;31: Key Words: compressive garment, DOMS, muscle soreness The Human Performance Laboratory, Ball State University, Muncie, Ind. Center for Sports Medicine, Pennsylvania State University, University Park, k. This project was supported in part by a grant from E.I. du Pont de Nemours and Company, Inc in Wilmington, Delaware and by Pennsylvania State University. Approved by the Institutional Review Board at the University. Send correspondence to William ). Kraemer, Human Performance laboratory, Ball State University, Muncie, IN wkraemer@bsu.edu T he idea that strenuous exercise can lead to muscle damage was first reported in the early 1900s by Hough.16 Subsequent studies revealed cellular and myofibril disruptions are greater following eccentric muscle actions compared to isometric or concentric contraction~.~.~~ Eccentric muscle damage results from mechanical stress, imbalances in muscle cell calcium homeostasis, or local inflammati~n.~.'~ Symptoms of muscle damage in eccentrically exercised muscles occur in all individuals, regardless of age or fitness level, but are accentuated in non-resistancetrained individuals. Clinically, the effects of strenuous eccentric exercise are manifested as impaired muscle function, including pain, swelling, decreased ability to generate tension, and loss of motion. Changes in various hormone and enzyme concentrations also reflect muscle damage. Creatine

2 kinase (CK), a general marker of muscle damage, is released with ischemic muscle damage (ie, myocardial infarction), muscle-wasting disease (muscular dystrophy, polymyositis), or intense exercise.18 Lactate dehydrogenase (LDH), present in the sarcoplasm, is also released into the bloodstream when individual muscle fibers are damaged.2.3 Cortisol, a hormone released by the adrenal cortex in response to stress, can be elevated or depressed depending on the intensity and duration of e~ercise.~-~'." Treatment of exercise-induced muscle soreness, like treatment of any other soft tissue injury, is focused on rest, ice, compression, and elevation (RICE) with the judicious use of oral nonsteroidal anti-inflammatory medications. Rest implies refraining from activity that increases pain in the injured area rather than a complete cessation of activity. Ice is used as an analgesic and to decrease local tissue metabolism. Compression has been used to reduce swelling,'g promote alignment of scar tissue,32 and provide proprioceptive input to the injured body part Intermittent compression temporarily decreased swelling and muscle stiffness but had no effect on the loss of strength observed in the eccentrically exercised m~scle.~ With regard to eccentric damage, no studies have yet examined the direct impact of limb elevation on symptoms related to delayed onset muscle soreness (DOMS). Elevation is used clinically, however, to reduce swelling in the dependent limb following soft tissue injury. No data are available to evaluate the efficacy of constant compression in reducing soreness, loss of motion, and decreased force production associated with eccentric exercise. In this study, we hypothesized that constant compression via the use of a compressive arm sleeve would reduce the severity and duration of soreness associated with DOMS. METHODS Approach to Experimental Problem Women with no weight lifting experience within the past 2 years performed an eccentric exercise program and were assigned to either the experimental or control group. Each subject could not act as her own control since prior studies showed a decrease in muscle damage in subsequent exercise bouts after a single exposure to high intensity eccentric exerci~e.'.~~ One group wore a compressive sleeve throughout the May recovery period. Experimental measures included soreness ratings, ease of performing daily activities, arm girth, resting elbow angle, elbow flexor strength, and blood samples for hormone and enzyme analyses. TABLE. Subject characteristics (mean 2 SE) for the experimental compressive sleeve (ECS) and control (C) groups. Characteristic ECS (n = 10) C (n = 10) Age (yrs) Height (cm) r ? 6.0 Weight (kg) r 5.6 Body fat (%I 22.7 r RM concentric arm curl strength (N-m) r 1.6 Subjects Twenty nonimpaired, non-strength-trained women who had not participated in any resistance training program for over 2 years volunteered to be subjects in this investigation. Subjects did participate in recreational fitness aerobic activities (eg, jogging, aerobic dance). Subjects were informed of the associated risks of the study and signed a consent form ap proved by the University's Institutional Review Board on Use of Human Subjects. Subjects were screened by a physician and were determined to have no orthopaedic, metabolic, or endocrine disorders that could influence the results of this study. In order to control for confounding therapeutic treatment effects, subjects were asked to refrain from taking medications, including nonsteroidal anti-inflammatory medications (aspirin, ibuprofen), acetaminophen, corticosteroids, sedatives, anticoagulants, and other prescription medications for a period beginning 2 weeks prior to the study and continuing throughout the study period. During the study, subjects were also asked to limit the water temperature and duration when bathing (ie, just wash arm without submerging), to use no therapeutic modalities including ice or heat massages, and to refrain from physical activity. Twenty women were matched based on age, height, weight, body fat percentage, and one repetition maximum (IRM) concentric strength and then randomly placed into 2 groups: experimental compressive sleeve (ECS) or control (C). The table describes the subject characteristics and matching profile. There were no significant (P < 0.05) differences between the 2 groups using an independent 2-tailed t test with appropriate alpha level (Bonferonni correc tions). Compressive Garment The subjects in the ECS group wore the compression sleeve (Figure 1) 24 hr-d-' over the entire May recovery period following the eccentric damage protocol. The compression sleeve was only removed for bathing the arm one time per day. The compressive garment was constructed of a Raschell fabric (7.7 o~sq yd-i) with 25% Lycra content. Circumference measurements of the garment (16 cm from top of garment) were taken before and while the subject J Orthop Sports Phys Ther.Volume 31.Number BeJune 2001

3 a 1 tal FIGURE 1. Example of experimental compresswe sleeve worn by subjects for 5 days after the eccentric-exercise damage protocol. wore the garment to determine the amount of garment stretch and compressive force exerted on the arm. There was a 9centimeter expansion of the compressive garment in the normal anatomical position. The compressive force, determined via pressure modeling, was 10 mm Hg. The garments were individually fitted for each subject in the experimental group prior to the eccentric exercise session. The garment covered the dominant arm from axillary line to mid-forearm. Preliminary Testing Anthropometric measurements (height, weight, 7 site skinfold measures) were obtained and percent body fat was determined via previously described method^.^.'^ All subjects were familiarized with the testing procedures days prior to the eccentric damage protocol to eliminate learning effects on strength tests. During this familiarization period sub jects did not perform eccentric contractions, so as not to confound the symptoms of soreness resulting from performing the maximal eccentric exercise protocol, but were carefully instructed on this important component of the study protocol. Three maximal concentric elbow flexion contractions were performed with the dominant arm at 60.sec-' on 2 sep arate occasions after familiarization, and test-retest reliability scored an intraclass correlation coefficient of R = Daily Questionnaire Subjects completed 2 questionnaires daily (AM and PM) throughout the study to assess their perception of difficulty performing daily activities requiring use of the dominant arm. The subjects rated the difficulty of completing various activities on a scale of 1-5 (1 representing greatest difficulty). This scale was previously used in clinical trials in our laboratory. Daily activities included brushing teeth, combing hair, eating, bathing, and doing laundry and household chores. These data were integrated into one toindicator of dominant arm function in daily activities by averaging the scores on all measures. A second set of questionnaires was completed each morning while at the laboratory. Subjects indicated their global assessment of soreness, soreness through active range of motion at the elbow joint, and soreness with manual palpation of the biceps muscle and tendon of the exercised arm on a visual analog scale using a single slash to mark the pain level. The scale was an unmarked line measuring 10 centimeters in length. The score was determined by the distance of the mark from 0 to 10, with 0 representing no soreness and 10 representing the greatest soreness. The subjects also gave an ordinal scale rating as to the degree of soreness (ie, 0 = no soreness. 1 = little soreness, 2 = some soreness, 3 = a lot of soreness, and 4 = as sore as can be) in each area. Measurements Resting blood sample, circumference of the dominant arm at the mid-humerus, relaxed elbow angle, and maximal elbow flexion strength were measured in that order each day between 0500 and 0800 beginning the day prior to exercise and continuing for 5 days following exercise. Circumference measurements were obtained with a spring-loaded flexible tape measure (Lafayette Instrument Co, Lafayette, Ind). Relaxed elbow angle was obtained while the subject was standing with the arms resting at the sides using a goniometer with one degree markings (Jamar, Clifton, NJ). Concentric elbow flexion strength was found via peak torque output (N-m) at 60"-sec-' on an isokinetic dynamometer (Biodex System 2, software version 4.5, Shirley, NY). Reference points for mid-humeral circumference (acromion J Orthop Sports Phys TherrnVolume 31.Number 6.June 2001

4 process and lateral epicondyle of the humerus) and elbow angle (midpoint of the acromion process and styloid process of the radius) were marked with indelible ink to maintain measurement precision. Nondominant mid-humerus circumference and relaxed elbow angle and dominant mid-femur circumference measurements were taken throughout the study to determine repeatability of measurements (test-retest, Intraclass Reliabilities were r 0.98)." Each day elbow flexion peak torque (N-m) and power (W) were determined via 3 maximal concentric contractions at 60.sec-' with the highest value used for analysis. Blood Collection and Analyses Each day of the study (preexercise and days 1-5 of recovery), a 20 ml venous blood sample was ob tained under sterile technique from the antecubital vein using a 20-gauge needle and Vacutainer set-up. Blood samples were obtained under resting, fasted conditions. Blood was centrifuged at 3000 rpm at 4 C and stored at -80 C prior to analysis. Blood was analyzed for serum CK, serum cortisol, and serum LDH. Serum CK was analyzed via ultraviolet spectrophotometry assay at 340 nm (Sigma Chemical Co, St. Louis, Mo). Serum cortisol was analyzed via a solidphase single antibody ImmuChem C~rtisol'~" radioimmunoassay (ICN Biomedicals Inc, Costa Mesa, Calif). Assay sensitivity was 0.2pg-dL-I. Serum LDH was analyzed via ultraviolet spectrophotometry assay at 340 nm (Sigma Chemical Co, St. Louis, Mo). All assays were performed in duplicate. For each assay, all samples were analyzed in the same assay; therefore, only an intra-assay variance of less than 5% was calculated. Eccentric Exercise Protocol The muscle damage protocol was performed on a Biodex System 2 isokinetic dynamometer set for passive motion at 60.sec-'. Each subject performed 2 sets of 50 repetitions with 3 minutes rest between sets. Every fourth repetition, the subject performed a maximal concentric contraction with an isometric hold at end range (to maximize response to the protocol) followed by an eccentric contraction in which the subject resisted mechanically forced elbow extension. The protocol was used to allow the subject adequate time to mentally prepare for a maximal effort in each eccentric muscle action and allow continuous uninterrupted movement. Immediately following the eccentric damage protocol, the subjects in the experimental group donned the compression garment. Again, the compression sleeve was removed only for study measurements and to wash the arm with no water flow directly on the arm for the duration of the study. Statistical Analysis The data were statistically evaluated by using a 2- way analysis of variance technique with repeated measures (groups X time).27 Statistical assumptions were tested (eg, tests for normality of distribution [KolmogorovSmirnov chi-square test] and homogeneity of variance [Levene's test]) prior to the analysis of variance. Post hoc comparisons were accomplished via Fisher's LSD.27 Statistical significance was chosen as P Using the nquery Advisor software version 2.0 (Statistical Solutions, Saugus, Mass), we determined the n size of 10 in each group produced a statistical power of at the 0.05 alpha level with effect sizes ranging from with the low being 0.2, middle 0.4, and high 0.8. Test-retest reliability using intraclass correlations was r 0.96 for all measurements obtained. RESULTS There was a significant decrease in peak torque (N-m) and power (W) production in both groups after exercise (recovery days 1-4 for the ECS group and days 1-5 for the C group). By day 3, however, the ECS group experienced less of a decrease in strength (Figure 2A) and power (Figure 2B) compared to the C group. There was a significant increase in upper arm circumference from preexercise to the fifth day of recovery in the C group ( cm increase), while the ECS group experienced no significant change in arm circumference measurements following the eccentric exercise (Figure 3A). While no visually apparent swelling was noted in the wrist or hand, circumference measurements of the wrist and volumetric determinations of the hand were not obtained in the present study. The ECS group also showed no significant change in resting elbow angle (% change in degrees from pre-exercise measurement), while the C group showed significantly greater elbow flexion at rest following eccentric exercise (64% change) (Figure 3B). The daily questionnaires indicated the subject's perception of soreness while performing daily activities. The results from the questionnaire were integrated into a total score (Figure 44). There was a perceived decrease in ability to perform daily tasks for both groups throughout the recovery period. By day 3, however, significant differences were observed between the 2 groups, with the ECS group indicating significantly greater ease in performing daily activities compared to the C group. Subjects in both groups had a significantly increased perception of soreness for the first 3 days following the eccentric exercise as derived from a Likert scale of soreness rating (Figure 4B). By day 4, the ECS group reported significantly less soreness. By day 2, the ECS J Orthop Sports Phys Ther*Volume 31.Number BeJune

5 B Pre Day 1 Day 2 Day 3 Day 4 Day S -1.0 b' / Day 1 Day 2 Day 3 Day 4 Day S Prc Day 1 Day 2 Day 3 Day 4 Day S FIGURE 2. Dominant elbow flexion peak torque (N-m) (Panel A) and peak power 0 (Panel 6) pre-exercise and during 5 days of recovery in the experimental compressive sleeve (ECS) and control (C) groups. Black horizontal lines above the bars indicate the span of significance. (*) indicates P from corresponding pre-exercise value; (+), P between ECS and C groups. group had significantly less perceived soreness during active elbow flexion and extension than the C group (Figure 4C). By day 3 post exercise, the ECS group reported significantly less soreness during palpation of the damaged tissue area (Figure 4D). No significant changes were observed in serum cortisol concentrations (nmol-l-i) (Figure 5A) or serum lactate dehydrogenase (U-L-I) concentrations (Figure 5C) throughout the recovery period. Serum CK concentrations (U-L-I) were significantly elevated over the May recovery period in both groups; differences between groups began occurring at day 2 (Figure 5B). While the CK response was elevated above baseline in the ECS group, the values were significantly lower than those found in the C group. DISCUSSION Eccentric exercise has been used to elicit muscle damage in order to study both the mechanism of tissue disruption and therapeutic interventions. In our study, compression was found to promote faster re- 2 v Day l Day 2 Day 3 Day 4 Day 5 FIGURE 3. Dominant upper arm circumference (% change in cm from pre-values) (Panel A) and dominant elbow angle (%change in degrees from pre-values) (Panel 6) preexercise and during 5 days recovery from maximal eccentric exercise in the experimental compression sleeve (ECS) and control (C) groups. (*) indicates P from corresponding preexercise value; (t), P between ECS and C groups. covery of force production, prevent swelling and loss of elbow extension at rest in the exercised arm, and allowed subjects to return to daily activities sooner. Subjects treated with the compressive sleeve also reported less pain at rest and during palpation of the exercised muscle. Delayed onset muscle soreness following novel exercise typically peaks hours after the exercise session. Muscle soreness is accompanied by muscle tissue damage characterized by decreased range of motion, pain with stretch and palpation of the exercised muscle, and swelling.6 Damage caused by eccentric exercise results from the high load placed on few fast-twitch muscle fibers leading to disruption of noncontractile structural ~omponents.~j~-~~ Muscle biopsies of eccentrically exercised muscle show Z line streaming,14 muscle fiber ~welling,2~.~~ mast cell degranulation,gj loss of intracellular structural proteins including desmin and dystr~phin,~.~~ the presence of fibronectin (an extracellular protein) within the and neutrophil infiltration." J Orthop Sports Phys Ther.Volume 31.Number BeJune 2001

6 Pre Day Day Day Day Day Pm Day 1 Day 2 Day 3 Day 4 Day 5 k d... VI E 0 0 V) ECS cmhd Day 3 Pre Day 1 Day 2 Day 4 Day 5 Pre Day 1 Day 2 Day 3 Day 4 Day 5 FIGURE 4. Integrated function (average of scores on all measures) of the normal daily activities (hnel A) (higher score represents better function in this panel), perceived soreness ratings for global assessment of soreness (hnel B), soreness with active range of motion (Panel C), and soreness with palpation (Panel D) for the experimental compression sleeve (ECS) and control (C) groups pre-exercise and during 5 days recovery from maximal eccentric exercise. Black horizontal lines above the bars indicate the span of significance. ('1 indicates P c 0.05 from corresponding pre-exercise value; (t), P c 0.05 between ECS and C groups. Inability to generate tension in the biceps muscle following the exercise protocol may be due to both pain (secondary to local accumulation of inflammatory agents) and structural damage in the muscle sarcomeres. The absence of swelling in the exercised muscle group and decreased soreness observed in the ECS group may have resulted from the compressive support provided by the sleeve. Additionally, the compression sleeve may serve as an external mechanical support to the muscle, thus facilitating a more rapid recovery of force production. The relaxed elbow angle was unchanged over the recovery period in the ECS group. Conversely, the C group held the exercised arm in a significantly greater amount of flexion (Figure 2B). This indicated that the amount of swelling was considerably less in the ECS group, which allowed for a greater anatomical difference in the relaxed position of the arm. The reduction in the amount of swelling most likely contributed to the higher amounts of function and reduced cellular damage to the contractile unit.' Compression thereby mediated the reduction in the swelling component of the eccentric exercise damage protocol. Clinically, such a therapeutic intervention may be helpful in the management of soft tissue injury. Creatine kinase and LDH have been shown to be released from damaged muscle tissue to the bloodstream and as such can be used as markers of muscle tissue damage. In our study, CK levels were elevated J Orthop Sports Phys Ther*Volume 31.Number 6.June 2001

7 ." Prc Day 1 Day 2 Day 3 Day 4 Day 5 Pre Day 1 Day2 Day 3 Day 4 Day 5 a Pre Day 1 Day 2 Day3 Day4 Day5. ECS U control FIGURE 5. Serum cortisol (nmo1.l-i) (Panel A), creatine kinase (UsL-I) (Panel B), and lactate dehydrogenase (U-L-I) (Panel C) concentrations for the ECS and C groups pre-exercise and recovery from maximal eccentric exercise. Black horizontal lines above the bars indicate the span of significance. (*) indicates PI 0.05 from corresponding pre-exercise value; (t), P I 0.05 between experimental compression sleeve (ECS) and control (C) groups. above baseline in both groups, although the ECS group had a significantly lower CK response compared to the C group. It might be speculated that the reduction in movement allowed quicker healing by attenuating the inflammatory response after the mechanical damage.6 Lactate dehydrogenase was not elevated above baseline in either group. This is consistent with work by Friden et al,ij who also found an elevation in serum CK with no change in serum LDH after eccentric exercise of the lower leg anterior muscle compartment. Brown et a12 described elevated CK and LDH following eccentric exercise of the knee extensors. Thus, LDH response may be due to the size of the muscle group affected by the eccentric exercise protocol. The differences in CK and LDH responses are most likely due to the structurally different areas in which they are sequestered within the muscle sarcomere and are dependent on the site of primary mechanical muscle damage. Serum cortisol concentration has been used as a classic marker of stress. Cortisol, released by the adrenal cortex, is elevated in response to stress and low muscle glycogen. Both the intensity and duration of the exercise play major roles in cortisol release. At lower exercise loads, serum cortisol may be elevated".*' or unchanged2' depending on these variables. With repetitive intensive training (> 100% increase over baseline activity), the observed decline in serum cortisol concentration may be the result of an inability of the adrenal cortex to keep up with demand.s4 Failure to observe an increase in serum cortisol in our study may indicate that the small muscle mass involved in the exercise was insufficient to elicit a whole body stress response to stimulate release of cortisol from the adrenal cortex. While the duration of exercise was insufficient to deplete muscle glycogen stores, it was anticipated that the influx of white blood cells to the damaged muscle tissue would lead to increased cortisol concentrations because white blood cells use glycogen as the primary nutritional source. 1 Orthop Sports Phys Ther.Volume 31.Number 6.June 2001

8 Despite the wide variety of therapeutic interventions used to treat DOMS (eg, low intensity concentric muscle acti~ns,~' cry~therapy,'~j"~ and intermittent compression5), no one treatment has yielded positive therapeutic results. An effective intervention following muscle damage would allow early mobilization of the injured area and provide compression to minimize swelling. The compressive sleeve used in this study allowed the subject to flex and extend the elbow during daily activities and prevented swelling in the arm. Earlier recovery of force production and decreased perception of soreness during activities and palpation may be due to support of the soft tissue in more normal alignment and thus the lack of swelling or increased blood flow through the area to facilitate removal of damage by-products. This type of "dynamic casting" allows for faster recovery of muscle function and promotes tissue repair. CONCLUSIONS In summary, this study provides data to support the use of compression as a therapeutic treatment for soft tissue injury. The use of the compressive garment following damaging exercise such as eccentric contractions may be speculated to provide an enhanced microenvironment for the healing process, thus facilitating recovery of muscle function via reduced swelling and promoting stable alignment of the muscle fibers. Future research needs to extend the use of this aspect of the RICE principle into the study of soft tissue injury. ACKNOWLEDGEMENTS The investigators would like to express their thanks to the subjects who made this study possible. In addition, our thanks go out to the laboratory staff and research assistants who helped in the data collection and analyses. Special thanks to Mr and Mrs John and Janice Fisher for support of the Human Performance Laboratory at Ball State University. REFERENCES Birmingham TB, Kramer JF, lnglis JT, et al. 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