Probing muscle recovery following downhill running using precise mapping of MRI T2 relaxation times

PURPOSE

Postexercise recovery rate is a vital component of designing personalized training protocols and rehabilitation plans. Tracking exercise-induced muscle damage and recovery requires sensitive tools that can probe the muscles' state and composition noninvasively.

METHODS

Twenty-four physically active males completed a running protocol consisting of a 60-min downhill run on a treadmill at -10% incline and 65% of maximal heart rate. Quantitative mapping of MRI T2 was performed using the echo-modulation-curve algorithm before exercise, and at two time points: 1 h and 48 h after exercise.

RESULTS

T2 values increased by 2%-4% following exercise in the primary mover muscles and exhibited further elevation of 1% after 48 h. For the antagonist muscles, T2 values increased only at the 48-h time point (2%-3%). Statistically significant decrease in the SD of T2 values was found following exercise for all tested muscles after 1 h (16%-21%), indicating a short-term decrease in the heterogeneity of the muscle tissue.

CONCLUSION

MRI T2 relaxation time constitutes a useful quantitative marker for microstructural muscle damage, enabling region-specific identification for short-term and long-term systemic processes, and sensitive assessment of muscle recovery following exercise-induced muscle damage. The variability in T2 changes across different muscle groups can be attributed to their different role during downhill running, with immediate T2 elevation occurring in primary movers, followed by delayed elevation in both primary and antagonist muscle groups, presumably due to secondary damage caused by systemic processes.

Use of a Non-Pharmacological Pain Relief Kit to Reduce Opioid Use Following Orthopedic Surgery: A Prospective Randomized Study

Introduction

Opioid prescription to treat pain among orthopedic surgery patients remains common practice in the United States but overprescribing opioids can lead to abuse. The purpose of this study was to determine the effect of a multimodal non-pharmacological 'pain relief kit' on pain, function, and opioid consumption in individuals recovering from orthopedic surgery.

Hypothesis

Patients provided with the pain relief kit would consume less opioid medication, report lower pain levels, and have better functional outcome scores than the control group.

Level of Evidence

2b.

Methods

Fifty-three subjects (18 women, 35 men) having orthopedic surgery were randomly assigned to either receive the Pain Relief Kit (treatment) or control group. At the first postoperative physical therapy visit (within 1 week of surgery) the treatment group was provided elastic resistance bands, kinesiology tape, Biofreeze, and a hot/cold pack as part of the Pain Relief Kit. Patients completed the SF-36 and either the DASH or LEFS questionnaires consistent with their surgery at baseline and four weeks post-op. Both groups reported daily pain (Visual Analogue Scale), opioid use, and over the counter medication use. The treatment group also recorded daily kit modality use.

Results

There was no significant difference in total opioid use between the treatment (108±252 milligram morphine equivalents) and control groups (132±158 MME; p=0.696). Opioid use and pain declined from week one to four with no difference between groups (p<0.001). Outcome scores and SF-36 scores improved from week one to four with no difference between groups (p<0.001).

Conclusion

A non-pharmacological pain relief kit did not have an effect on opioid use in this patient population nor did it improve pain relief or function compared to controls.

The cold truth: the role of cryotherapy in the treatment of injury and recovery from exercise

Cryotherapy is utilized as a physical intervention in the treatment of injury and exercise recovery. Traditionally, ice is used in the treatment of musculoskeletal injury while cold water immersion or whole-body cryotherapy is used for recovery from exercise. In humans, the primary benefit of traditional cryotherapy is reduced pain following injury or soreness following exercise. Cryotherapy-induced reductions in metabolism, inflammation, and tissue damage have been demonstrated in animal models of muscle injury; however, comparable evidence in humans is lacking. This absence is likely due to the inadequate duration of application of traditional cryotherapy modalities. Traditional cryotherapy application must be repeated to overcome this limitation. Recently, the novel application of cooling with 15 °C phase change material (PCM), has been administered for 3-6 h with success following exercise. Although evidence suggests that chronic use of cryotherapy during resistance training blunts the anabolic training effect, recovery using PCM does not compromise acute adaptation. Therefore, following exercise, cryotherapy is indicated when rapid recovery is required between exercise bouts, as opposed to after routine training. Ultimately, the effectiveness of cryotherapy as a recovery modality is dependent upon its ability to maintain a reduction in muscle temperature and on the timing of treatment with respect to when the injury occurred, or the exercise ceased. Therefore, to limit the proliferation of secondary tissue damage that occurs in the hours after an injury or a strenuous exercise bout, it is imperative that cryotherapy be applied in abundance within the first few hours of structural damage.

Associations Between Skin Surface Temperature and Pressure Pain Tolerance Thresholds of Asymptomatic Individuals Exposed to Cryotherapy and Thermotherapy

Objective

The purpose of this study was to evaluate associations between skin surface temperature and pressure pain tolerance thresholds (PPTs) of asymptomatic individuals exposed to cryotherapy and thermotherapy.

Methods

Twenty-two asymptomatic female university students aged between 18 and 35 years underwent thermography and algometry assessments at 6 points in both knees before, immediately after, and 20 minutes after the application of frozen (cryotherapy) or heated (thermotherapy) gel bags in the right knee for 20 minutes. Data were analyzed by 1-way analysis of variance, Student t test, and Pearson or Spearman correlation tests.

Results

There was a significant change in skin surface temperature after cryotherapy and thermotherapy, which was maintained after 20 minutes of withdrawal (P < .001). After the intervention, no significant differences were observed regarding PPT compared with the baseline measurements, nor between the experimental and control knees.

Conclusion

Cryotherapy and thermotherapy produced significant changes in the temperature of the evaluated points after their application. No differences in pain tolerance were observed in these asymptomatic participants. There was little association between skin surface temperature and PPT in the knees of healthy women after application of the resources.

Pain Tolerance: The Influence of Cold or Heat Therapy

Objectives

Resources of heat or cold therapies have been widely used for their low cost, analgesic action and for assisting the rehabilitation of acute or chronic injuries. The objective of this study was to search for associations between skin surface temperature and pressure pain tolerance thresholds (PPTs) of healthy individuals undergoing cryotherapy and thermotherapy.

Methods

This is an experimental clinical trial with 22 healthy university students aged between 18 and 35 years. Volunteers underwent thermography and algometry assessments at 6 points in both knees before, immediately after, and 20 minutes after the application of frozen (cryotherapy) or heated (thermotherapy) gel bags in the right knee for 20 minutes. Data were analyzed by 1-way analysis of variance, Student's t test, and Pearson or Spearman correlation tests.

Results

There was a significant change in skin surface temperature after cryotherapy and thermotherapy, which was maintained after 20 minutes of withdrawal (P < .001). After the intervention, no significant differences were observed regarding the PPT compared to the baseline measurements, nor between the experimental and control knees.

Conclusion

Cryotherapy and thermotherapy produced significant changes in the temperature of the evaluated points after their application. Despite this, no differences in pain tolerance were observed, and there was little association between skin surface temperature and PPT in the knees of healthy women after application of the resources.

Cryotherapy associated with tailored land-based exercises for knee osteoarthritis: a protocol for a double-blind sham-controlled randomised trial

INTRODUCTION

There is an unmet need to develop tailored therapeutic exercise protocols applying different treatment parameters and modalities for individuals with knee osteoarthritis (KOA). Cryotherapy is widely used in rehabilitation as an adjunct treatment due to its effects on pain and the inflammatory process. However, disagreement between KOA guidelines remains with respect to its recommendation status. The aim of this study is to verify the complementary effects of cryotherapy when associated with a tailored therapeutic exercise protocol for patients with KOA.

METHODS AND ANALYSIS

This study is a sham-controlled randomised trial with concealed allocation and intention-to-treat analysis. Assessments will be performed at baseline and immediately following the intervention period. To check for residual effects of the applied interventions, 3-month and 6-month follow-up assessments will be performed. Participants will be community members living with KOA divided into three groups: (1) the experimental group that will receive a tailored therapeutic exercise protocol followed by a cryotherapy session of 20 min; (2) the sham control group that will receive the same regimen as the first group, but with sham packs filled with dry sand and (3) the active treatment control group that will receive only the therapeutic exercise protocol. The primary outcome will be pain intensity according to a Visual Analogue Scale. Secondary outcomes will be the Western Ontario & McMaster Universities Osteoarthritis Index; the Short-Form Health Survey 36; the 30-s Chair Stand Test; the Stair Climb test; and the 40-m fast-paced walk test.

ETHICS AND DISSEMINATION

The trial was approved by the Institutional Ethics Committee of Federal University of São Carlos, São Paulo, Brazil. Registration approval number: CAAE: 65966617.9.0000.5504. The results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03360500.

Rapid Facial Cryotherapy for Combat Sports: A Comparison of Materials and Methods for Cooling Facial Tissues in 60 Seconds or Less

CONTEXT

Athletes in combat sports who have sustained facial hematomas during competition have traditionally been treated with an enswell. These treatments take place between rounds of the competition and generally last less than 60 seconds. The efficacy of this modality has not been studied. Other modalities may provide a more effective cryotherapy treatment in this timeframe.

OBJECTIVE

To compare the efficacy of different forms of rapid cryotherapy to cause surface temperature changes of the face within 60 seconds of application.

DESIGN

Crossover study.

SETTING

Laboratory.

PARTICIPANTS

Eleven healthy men (age 21.73 [1.42] y, mass 82.1 [5.6] kg, height 177.2 [7.0] cm).

INTERVENTIONS

A 60-second treatment using chilled surgical steel enswell, copper, commercial cold pack, aluminum, brass, ice cube, ice pack, and saltwater pack.

MAIN OUTCOME MEASURES

Preintervention and postintervention surface facial temperatures.

RESULTS

The ice bag, cold pack, ice cube, saltwater pack, and stainless-steel enswell caused statistically different temperatures preintervention to postintervention. The ice bag and saltwater pack cause statistically greater cooling than the other materials tested.

CONCLUSIONS

This study does not support the clinical use of an enswell to provide short-duration cryotherapy treatments to facial tissue, as ice packs are more effective.

Short-term cryotherapy did not substantially reduce pain and had unclear effects on physical function and quality of life in people with knee osteoarthritis: a randomised trial

OBJECTIVE

Does short-term cryotherapy improve pain, function and quality of life in people with knee osteoarthritis (OA)?

DESIGN

Randomised controlled trial with concealed allocation, blinded assessment of some outcomes, and intention-to-treat analysis.

PARTICIPANTS

People living in the community with knee OA.

INTERVENTIONS

The experimental group received cryotherapy, delivered as packs of crushed ice applied to the knee with mild compression. The control group received the same regimen but with sham packs filled with sand. The interventions were applied once a day for 4 consecutive days.

OUTCOME MEASURES

Participants were assessed at baseline and on the day after the 4-day intervention period. The primary outcome was pain intensity according to a visual analogue scale. Secondary outcomes were baseline to post-intervention changes according to the Western Ontario and McMaster Universities Osteoarthritis, Knee injury and Osteoarthritis Outcome; Timed Up and Go test; and 30-Second Chair to Stand test.

RESULTS

Sixty participants were randomised into the experimental group (n = 30) or the control group (n = 30). Twenty-nine participants from each group completed the trial. The mean between-group difference in change in pain severity was -0.8 cm (95% CI -1.6 to 0.1), where negative values favour the experimental group. This result did not reach the nominated smallest worthwhile effect of 1.75 cm. The secondary outcomes had less-precise estimates, with confidence intervals that spanned worthwhile, trivial and mildly harmful effects.

CONCLUSION

Short-term cryotherapy was not superior to a sham intervention in terms of relieving pain or improving function and quality of life in people with knee OA. Although cryotherapy is considered to be a widely used resource in clinical practice, this study does not suggest that it has an important short-term effect, when compared with a sham control, as a non-pharmacological treatment for people with knee osteoarthritis.

REGISTRATION

NCT02725047.

Cold water immersion settings for reducing muscle tissue temperature: a linear dose-response relationship

BACKGROUND

Although cold water immersion (CWI) is widely accepted and integrated as a recovery modality in sports practice, questions regarding its proposed working mechanisms remain. This study systematically reviews the existing literature on one the proposed mechanisms of CWI, its effect on muscle tissue temperature, and subsequently tries to identify a dose-response relationship in order to describe an optimal dose.

EVIDENCE ACQUISITION

A systematic literature search (PubMed and Sport Discus) was conducted in October 2017. Dose-response relationships were analyzed using linear regression while controlling for possible confounders (muscle measurement depth and immersion position).

EVIDENCE SYNTHESIS

A total of 10 studies, with a total of 104 participants, were included utilizing 26 different CWI protocols. Muscle tissue temperatures were reduced significantly by 24 CWI protocols. A significant, relationship with a medium effect size (r=0.51) was identified between muscle tissue temperature and CWI. The most optimal dose-response relationship, with a large effect size, (r=0.87) was described for CWI protocols using full-body immersion at a measurement depth of 30 mm (y = 4.051 x + 0.535).

CONCLUSIONS

CWI can decrease muscle tissue temperature significantly if a minimum CWI dose of 1.1 is applied, corresponding with an immersion of 11 minutes with a water temperature of 10 °C.

Effects of cryotherapy methods on circulatory, metabolic, inflammatory and neural properties: a systematic review

Abstract Introduction: The cooling therapy (cryotherapy) is commonly used in clinical environmental for the injuries treatment according to its beneficial effects on pain, local inflammation and the recovery time of patients. However, there is no consensus in the literature about the effects of cryotherapy in the physiological reactions of affected tissues after an injury. Objective: To realize a systematic review to analyze the cryotherapy effects on circulatory, metabolic, inflammatory and neural parameters. Materials and methods: A search was performed in PubMed, SciELO, PEDro and Scopus databases following the eligibility criteria. Included studies were methodologically assessed by PEDro scale. Results: 13 original studies were selected and presented high methodological quality. Discussion: The cryotherapy promotes a significant decrease in blood flow, in venous capillary pressure, oxygen saturation and hemoglobin (only for superficial tissues) and nerve conduction velocity. However, the effect of cryotherapy on the concentration of inflammatory substances induced by exercise, as the creatine kinase enzyme and myoglobin, remains unclear. Conclusion: The physiological reactions to the cryotherapy application are favorable to the use of this therapeutic tool in inflammatory treatment and pain decrease, and demonstrate its importance in the neuromuscular system injuries rehabilitation.