A double-blind, randomised, placebo-controlled study to evaluate the effect of orally-dosed LipiSperse curcumin and/or palmitoylethanolamide (PEA) on exercise recovery in healthy males.

INTERVENTION: Product 1, LipiSperse Curcumin: Each dose will contain 500 mg of curcumin consumed as a drink Product 2, PEA: Each dose will contain 150 mg of PEA consumed as a drink This is a double‐blind, randomised, clinical trial with a 72‐hour treatment duration with 3 arms (2 active ingredient arms and 1 placebo arm). Participants will be recruited from databases and public media outlets. Following preliminary screening via telephone, potential participants will attend the clinic for an information session and will be required to provide their consent for inclusion in the trial. Consenting participants will undergo a health assessment including lifestyle, current medications and medical history; this data will be used for the comprehensive screening and to provide contextual data for the study. Once enrolled in the trial, participants will be randomly allocated to either the placebo comparator group or one of two active intervention groups. Prior to treatment, participant’s blood will be collected (20 mL) for analysis. Specifically, myoglobin, creatine kinase, lactate dehydrogenase, lactate, CRP, IL‐6, IL‐10, TFN‐a, P38, antioxidant potential including glutathione, curcumin and/or PEA concentration, ELF/T and FBC. Participants will be asked to consume the allocated product according to the dose prescribed. An opaque packet will be provided to the study coordinator with group allocation and the contained powder will be mixed with 250 ml of water. Each packet will contain 1 g of study product (500 mg Lipisperse curcumin and 500 mg of maltodextrin, 150 mg of PEA and 850 mg of maltodextrin, or 1 g of maltodextrin) which is colour and flavour matched (orange). Following this (30‐60 minutes), participants will undergo a bout of exercise to induce local muscle fatigue. To reduce the risk of injury, participants will complete an adequate warm‐up consisting of stretching of major muscle groups and 5‐10 minutes of easy cycling (60 rpm, 5 RPE) on a cycling ergometer before attempting any exercise. Muscle fatigue will be induced using leg press and completion of 4 sets for as many reps as possible with a 2‐minute rest in between sets. First, a participant’s maximum leg press strength will be measured before they complete 4 sets of as many reps as possible at 80% of maximal leg press. Once a participant has completed the 4 sets, the participant will consume the supplement (placebo or active) and rest. Movement within this period will be limited to walking limited distance and sitting. Following a 90‐120‐minute rest period, the participant will again complete leg press reps at 70% of maximal until exhaustion. The number of reps completed will be converted to a percentage out of 50 reps to calculate performance. A power meter will also be used to measure maximum leg press repetition velocity and power, average velocity and power, and total work performed and each participant completes for a repetition of leg press by the time it takes them to perform it. Although absolute weight moved is valuable data, power, rate of force production, acceleration, velocity, and deceleration are useful in determination of movement and muscular kinetics. Leg press strength will be measured by Alistair Mallard, or a qualified professional hired by RDC Global. The gold standard, and common practice, 1 RM testing protocol will be used. After warming up, the load will be set at 90% of the predicted 1 RM, and increased after each successful lift until failure. Periods of rest (approximately 3–5 min) will be allotted between each attempt to ensure recovery. A test will be considered valid if the subject uses proper form and completes the entire lift in a controlled manner without assistance. A warm‐down will occur after exercise sessions by repeating the same protocol as the warm‐up. During each exercise component of the trial, correct form will be taught and constantly assessed by the administrator to help reduce the risk of injury. In the event that an injury is experienced, participants are to consult with the trial coordinator as soon as possible. For every visit to RDC Global, water will be available as desired (this includes the period prior to arriving). Water intake is expected to have no influence on the results of this trial. Further blood will be taken from participants immediately after the muscle fatigue sets, during the rest period, immediately before and after the performance trial and 60 minutes after the performance trial. Blood will also be taken at 24, 48 and 72 hours post exercise. Participants are asked to refrain from any strenuous activity for the 96 hours of the study protocol. Muscle soreness will be assessed at baseline and 24, 48 and 72 hours post exercise by a VAS and questionnaire. Thigh circumference will be measured using a tape measure at the mid‐point between the top of the knee (patella) and the crease at the top of the thigh. CONDITION: Exercise recovery PRIMARY OUTCOME: Change in creatine kinase via serum assau SECONDARY OUTCOME: C‐reactive protein as a measure of inflammation and antioxidant capacity via serum assay change in lactate dehydrogenase via serum assay Change in myoglobin via serum assay Fatigue as measured by Multidimensional symptoms fatigue inventory Gastrointestinal Tolerance scale ‐ a questionnaire used in other studies to assess the tolerance of supplements IL‐10 as a measure of inflammation and antioxidant capacity via serum assay IL‐6 as a measure of inflammation and antioxidant capacity via serum assay Muscle pain (Delayed on‐set muscle soreness) measured by VAS pan score Muscle swelling as measured by participant thigh circumference P38 as a measure of inflammation and antioxidant capacity via serum assay Pain as measured by KOOS/McGill pain Serum curcumin via serum assay serum lactate as a measure of inflammation and antioxidant capacity serum PEA concentrations via serum assay TNF‐a as a measure of inflammation and antioxidant capacity via serum assay INCLUSION CRITERIA: Recreationally trained males (150 minutes of exercise per week and 6 months of resistance training experience in the last year) between 18 and 35 years old Normal dietary habits (no medically prescribed diet, no slimming diet, no vegan or macrobiotic diet) Otherwise healthy, BMI 18.5‐35 Able to provide informed consent