An evaluation of the effects of a topical traditional Chinese medicine formulation on muscle soreness associated with athletic training

This project will evaluate the efficacy of a traditional Chinese medicine Cheong Kun Oil for reducing delayed onset muscle soreness (DOMS), the muscular pain and discomfort commonly experienced after a bout of unaccustomed exercise or activity. Cheong Kun Oil is a topical preparation which has been marketed in Macau since the 1960’s for its beneficial effects on muscle pain due to exercise, strains and injuries. This study will scientifically investigate the efficacy of Cheong Kun Oil for reducing DOMS in the thigh muscles after eccentric exercise (exercise where the muscle is lengthened) in healthy, young, well trained males. Design: Randomised, double-blind placebo controlled trial. Intervention As this study is a cross over design, the intervention below will be repeated twice (once on each leg) separated by 6 weeks to minimise the repeated bout effect (the familiarisation session will only occur once). A 6 week wash out period was chosen, as it has been reported that 6 weeks between eccentric exercise trials was effective to wash out any systemic inflammatory responses that would have developed in the first trial, and this wash-out period has been used successfully in other DOMS related studies. Participants will be stratified based on leg dominance before being randomized to the active or placebo group by a computer generated randomization chart that will be compiled by an independent researcher. Study Overview Session 1: collection of basic demographic details and familiarisation of all outcome measures (detailed below). Time commitment: 1 hour Session 2: Baseline testing (all outcome measures), eccentric exercise protocol, post testing (all outcome measures). Time commitment: 2 hours Session 3: 4 hours post baseline testing, all outcome measures will be reassessed. Time commitment: 30 min Session 4: 24 hours post baseline testing, all outcome measures will be reassessed. Time commitment: 30 min Session 5: 48 hours post baseline testing, all outcome measures will be reassessed. Time commitment: 30 min Session 6: 72 hours post baseline testing, all outcome measures will be reassessed. Time commitment: 30 min Session 7: 96 hours post baseline testing, all outcome measures will be reassessed. Time commitment: 30 min Methodology Details Session 1: After a full explanation of the study protocol, participants will be asked to complete stage 1 of the ESSA pre-exercise screening tool, provide written informed consent, and have their body mass, height and training history recorded. The participants dominant leg will be recorded, which will be used for stratification of participants prior to randomisation. Participant will be taken through the following outcome measures which will be assessed at all time points throughout the study: Primary Outcome measure Muscle pain: Pain will be assessed using a visual analogue scale (VAS) in the subject’s quadriceps. The VAS will be presented on an A4 piece of paper with a 100mm line printed in the middle of the page. The line will range from 0 (no pain) to 100 mm (worst possible pain) Participants will be asked to complete a body weight squat, and rate their muscle soreness. A body weight squat will be utilised, as there is generally no pain experienced due to unaccustomed activity such as eccentric exercise when the muscles are not actively engaged in movement. This subjective pain assessment has been used by numerous studies as a reliable and valid method of assessing acute pain. Secondary Outcome Measures Muscle Damage: Will be assessed through salivary creatine kinase, and indicative marker of exercise induced muscle damage. Passive drool saliva samples will be collected at all time points to assess the extent of muscle damage as identified through changes to creatine kinase levels. Saliva will be collected in sterilised cryovials via passive drool using saliva collection aids (Salimetrics) and stored in -20 °C freezer. Muscle tenderness: A pressure algometer will be used to monitor pressure induced pain at five specific sites on the quadriceps. Specific sites for assessment were determined using a reference system involving two anatomical points [anterior superior iliac spine (ASIS) and superior pole of the patella (SPP)]. All measurements will be taken on the right side whilst the participants lay supine on a plinth The measured sites will be: 15 cm distal to the ASIS, 4 cm proximal to the SPP, midpoint of the ASIS and SPP along the axis, then 2 cm lateral and 2 cm medial of this midpoint. These points of assessment were validated by a reliability study conducted by CI Pumpa, and the algometer has been validated in other studies. Muscle function: Maximal force generating capacity will be measured as maximal isokinetic concentric and eccentric knee extension peak torque at 60°·sec-1. Participants will complete 3 maximal isokinetic concentric muscle contractions, separated by 1 min on both the intervention and control leg, before completing 3 maximal isokinetic eccentric muscle contractions, separated by 1 min on both the intervention and control leg. This assessment of muscle function has been deemed valid and reliable. Range of Motion: Range of motion (ROM) at the hip and knee joints will be assessed using a goniometer. A goniometer is a non-invasive standard device for measuring angles, Passive hip and knee flexion and extension will be assessed on all participants using standardised protocols. Three trials for each movement will be recorded, and the median value used for analysis. Inflammation: An anthropometric measuring tape will be used to measure mid-thigh circumference, the midpoint between the anthropometric sites trochanterion and tibiale laterale. Circumference measurements will be used as an indicator of acute changes in thigh volume likely to occur from osmotic fluid shifts or inflammation, which is often associated with muscle damage and eccentric exercise. To identify adverse skin reactions, the repeated open application test (ROAT) will be employed in this study. This visual assessment test is commonly employed to evaluate whether a topical application results the development of red skin, dry skin, itching or frank dermatitis that are all indicate varying degrees of allergy. Session 2 All outcome measures noted above will be replicated before and immediately after the following the muscle damage protocol. Participants will perform a protocol consisting of 300 eccentric unlilateral repetitions (20 sets, 15 reps per set with 30 seconds between sets) with the quadriceps muscle group at a speed of 30°·sec-1. The protocol has been shown to effectively induce myofibrillar disruption and induce DOMS. After the post eccentric exercise assessments, participants will receive a 38mL bottle of Cheong Kun oil (or placebo), after being randomized to the active or placebo group by a computer generated randomization chart that will be compiled by an independent researcher. The oils will be provided in a plain opaque bottle with the subjects name and application regime displayed. The tubes and labeling will be completed by an individual not involved with the project, and the oil within the tubes will be identical in appearance and texture to ensure double blinding. The following directions will be printed on the label: For Topical application only 1. Apply 5 drops of oil onto affected area ONCE daily before bed prior to each training session for 6 days (evening before session 2-7) 2. The oil had to be rubbed with massage in circular motion for 5 mins 3. Until feeling of heat sensation and the oil is completely absorbed Participants will be asked at each follow-up session regarding the application of the oil the previous evening, and each tube will be weighed before distribution, and reweighted at the 96 hour time point to double-check compliance. Sessions 3-7 Participants will return to the laboratory to complete all assessments associated with the outcome measures noted above but on the opposite leg.