Profiling the acute post-exercise biochemical environment in trained athletes

Exercise and Sports Science Australia’s Adult Pre-exercise Screening Form: You will be required to complete this screening questionnaire to determine if you are ready to begin light/moderate intensity physical activity or if guidance from a health professional is required prior to commencing. Consent Form: If you decide to participate in this study, a consent form will be signed prior to any study assessments being performed. Cardiovascular Risk Factor Questionnaire: A cardiovascular risk factor questionnaire will be completed prior to any study assessments. Body Composition: A dual energy X-ray absorptiometry scan (DXA) is a specialised X-ray technique to provide a measure of body composition. Participants lay facing up on the scanning bed for the duration of the scan. This is just like a normal X-ray, with no pain involved and it will measure total body mass, fat mass and lean mass. The scan lasts for 7-8 minutes and participants will be scanned wearing light clothing one week prior to the exercise and nutrition intervention. A qualified technician will co-ordinate all DXA scans. Strength and Power Testing Maximum muscular strength of Group 1 will be determined during a series of one-repetition maximum (1RM) attempts. The 1RM attempts will be performed on the barbell back squat and deadlift. Following an appropriate warm-up for each selected exercise, a single repetition will then be performed with 5 minutes recovery periods between each attempt until the repetition load, that can be completed once but not a second time, is determined. The 1RM testing will only be performed by powerlifters, and will serve as the basis for prescribing exercise intensities. Mr. Shamim and Dr. Camera will co-ordinate all strength testing. VO2Peak Test The VO2max test is an incremental test to exhaustion on a stationary cycle ergometer. The workload increases every 2½ minutes until you can no longer maintain a pedaling rate of 60-70 rpm. This test is expected to last between 10-15 minutes. During the test, expired air is sampled as breaths are taken into a mouthpiece attached to an automated gas analyzer. The results from this test will provide a peak oxygen consumption reading, peak power output (PPO), and physiological data regarding cardiovascular health and fitness. The VO2max test will only be performed by cyclists and healthy age-matched individuals, and will serve as the basis for prescribing exercise intensities and representation of fitness, respectively. Mr. Shamim and Dr. Camera will co-ordinate all VO2max testing. Dietary Standardisation Prior to the trial day, all participants will consume a standardized meal provided by our research team based on personal preferences and presence of any known allergies. The diet will consist of 15-25% energy from protein, 45-65% energy from carbohydrate and 20-35% energy from fat. This distribution of macronutrient intake will ensure adequate energy to meet requirements outlined in the Australian Dietary Guidelines Acceptable Macronutrient Distribution Ranges (AMDR) for protein, carbohydrate and fat (expressed as a percentage contribution to total energy intake). In addition, a standardized breakfast will be served to all participants the morning of the trial. This meal will consist of similar macronutrient percentages as outlined above. Blood Sampling Two 50 mL samples of blood will be taken through venepuncture before, and after the exercise and nutrition intervention. This volume (total = 100 mL) is minimal compared to the standard 500 mL for a Red Cross donation. The 50 ml of blood collected on the two occasions is a volume equal to ~1% of total blood volume. Following the first blood draw, a standardized breakfast will be provided by the CEN before commencement of exercise to replenish fluid loses. In addition, light refreshments will also be provided by the CEN after the second blood sample to replenish the loss in blood volume. Exercise Intervention Participants in the Strength training (Group 1) and Endurance training (Group 2) will perform an acute bout of exercise, respective to their training discipline, while age-matched recreationally-trained participants (Group 3) will serve as a non-exercise control. Following a standardized breakfast, participants will rest for 90 minutes in a seated position. Subsequently, participants in Group 1 and 2 will complete their respective 90 minute exercise bout, followed by a 30 minute post-exercise rest before the final blood sample. Conversely, participants in Group 3 will continue to rest for 2 hours until the final blood sample. All participants will undertake pre-testing and measures of body composition one week prior to the trial. All preliminary testing and exercise sessions will occur at the ACU gym under the supervision of Mr. Shamim and Dr. Camera. Both Mr. Shamim and Dr. Camera possess the appropriate Fitness Instruction qualification to safely teach through all the different exercise types. Participants will be allocated to one of the following three experimental groups based on training status: Group 1: Strength Trained Athletes Participants in Group 1 will consist of well-trained, drug-free, powerlifters who have achieved an Elite II three-lift total by the International Powerlifting Federation standards and have been training for a minimum of two years prior (>4 training sessions per week for previous 6 months). The acute exercise intervention will replicate a typical leg-training session for these athletes, and consist of the sets, repetitions, and intensities for movements outlined below. The duration of the exercise session, including adequate warm-ups, will be ~90 minutes. • Acute Exercise Session: 1. Barbell back squat – 5 x 5 @ 75% 1RM 2. Deadlift – 3 x 3,2,1 @ 80, 85, 90% 1RM 3. Romanian Deadlift – 2 x 20 @ 50% 1RM Group 2: Endurance Trained Athletes Participants in Group 2 will consist of well-trained, drug-free, cyclists who have a VO2max > 65 mL/kg/min, competitively race at least A grade Victorian Road Series events, and have been training for a minimum of two years prior (>200 km/wk for previous 6 months). The acute exercise intervention will replicate a typical cycling session for these athletes, and consist of a combination of steady state cycling, interspersed with high-intensity sprint efforts performed on a stationary cycle ergometer, as described below. The duration of the exercise session, including adequate warm-up, will be ~90 minutes. • Acute Exercise Session: 1. 90 minutes continuous cycling at 70% of VO2Peak a. 60 second sprint efforts at 100% VO2Peak will occur every 10 minutes throughout the 90 minute protocol (i.e. 9 sprints) Group 3: No Exercise Control Participants in Group 3 will consist of participants with no previous history of performing exercise, but are otherwise healthy and age-matched to participants in either of the exercise groups. Participants in Group 3 will remain at rest for the length of the ~90 minute exercise bout performed by Groups 1 and 2.