The Effects of Various High-Intensity Combined Resistance and Aerobic Training on Physical and Perceptual Outcomes in Recreationally Active Adults.

7-weeks of High-Intensity Multimodal Training (HIMT) or Inter-session Concurrent Training (CT). This is a 2-arm randomised parallel trial (HIMT [intervention] v. CT [comparator]). What, how and where and when: What, how and where and when: The HIMT group will perform 4 HIMT sessions (i.e., combined high-intensity aerobic and resistance/ bodyweight exercise during a single session). The rationale for this frequency is to enable participants meet physical activity guidelines across both training modes. Training sessions will vary each week to sustain variety and interest. Participants will be encouraged to take a rest day after 2 consecutive training days to promote appropriate recovery. Training will be conducted face to face in small groups (3-8 participants) at participants' choice of training location: - UTS Moore Park - Neutral Bay F45 - Yowie Bay Scout Hall In the event more than 8 participants are scheduled into a session, an additional instructor will be involved in session delivery to maintain this supervision ratio (1:8). Training sessions will involve: HIMT programs will be matched to the comparator for weekly frequency, duration (total and net work), exercise selection, and prescribed intensity. Participants will be asked to refrain from participation in additional high-intensity aerobic and/ or resistance exercise and competitive/ recreational sport during the study. HIMT programs will commence each session with a 5 minute warm up circuit using bodyweight resistance or 50% of working weight or ergometer resistance (for exercises using external weight or ergometers) involving all major muscle groups followed by dynamic stretching. Session instructors will then provide a group overview of the session format including exercise selection, order, approximate prescribed or target volume (determined from familiarisation sessions during baseline testing) and prescribed intensity (i.e., 7/10 RPE). Instructors will clearly explain the session format (i.e., circuits), demonstrate each exercise and provide appropriate exercise technique cues. Sessions will finish with an instructor led 5 minute cool down including static stretching. Frequency: HIMT: 4 x 45 minute sessions/ week that are repeated Session Duration: Total 45 minutes (includes ~5 minute warm up and cool down) Session Format: Exercises will be performed in a circuit format during a session. Sessions may involve one or more circuits to ensure variety. Exercise Selection: Each training week will include the following movement patterns: hinge, squat, rotation, push, pull, hold. Exercise selection will change weekly to ensure variety and progressive overload. HIMT and comparator sessions in a training week will be matched for exercise selection. Exercise Equipment: HIMT and comparator programs will use the same exercise equipment as exercise selection is matched across a training week. All training locations will have access to the same equipment to ensure standardisation. Exercise equipment will include ergometer machine (e.g., cycle and row ergometers), free weights (e.g., dumbbells, kettlebells, medicine balls). Exercise equipment (i.e., exercise selection) will vary fortnightly to ensure variety. Exercise Order: Exercises will be ordered in a session to reduce fatigue across muscle groups (i.e., alternate lower body/ upper body exercises). Prescribed Volume: Total and net volume will be matched for CT and intervention protocols during a training week. Time based volume prescription will be primarily utilised (e.g., 45 seconds of work with 15 seconds of rest to transition to next exercise. Work to rest ratios will vary throughout the program to ensure variety. Work to rest ratios will increase across the program as a means of progressive overload. The initial starting weights or ergometer resistance for participants will be prescribed by the student researcher based on the training volume-load completed in baseline testing/ familiarisation sessions. Prescribed Intensity: Participants will be instructed to work at an RPE = 7/10 (‘very hard’) to ensure high-intensity activity. Participants will be familiarised with the RPE scale during baseline testing Days 2, 3 and 4. Aerobic exercises (e.g., ergometer): Participants will be instructed to: • “Work as hard as you can to maintain a =7/10 RPE” • “You should not be able to hold a conversation during the work period” • “You should be able to regain your breath within the rest period and move to the next station appropriately.” Resistance exercises (e.g., weights or bodyweight) : • “Aim to complete 10 reps using the heaviest weight you can for this rep range maintaining a = 7/10 RPE.” • “Perform each exercise with at least a 2 second lower and 1 second lift.” • “If you finish the 10 reps before the work period is over - that is okay you can rest for the remaining time rather than performing more reps if you achieved = 7/10 RPE.” • “If you do not reach = 7/10 RPE by 10 reps, complete more reps so that you achieve this RPE, and then increase your external load for the next set as guided by your instructor (e.g., 9kg DB goblet squat, increase to 10kg DB goblet squat).” • “You should aim to feel like you have 3 reps left in the tank for each set”. 10 reps was chosen to reflect common prescription in HIMT (i.e., ~10RM, strength-hypertrophy stimulus). Tempo: Aerobic exercises (e.g., ergometer): Participants will be instructed to: • “Work as hard as you can to maintain a = 7/10 RPE” Resistance exercises (e.g., weights or bodyweight) : • “Perform each exercise with at least a 2 second lower and 1 second lift.” This tempo is prescribed for resistance exercises to ensure appropriate exercise technique and safety. Monitored Volume: The training volume-load (i.e., weight lifted in resistance exercises x reps completed or distance covered x ergometer resistance) will be recorded each session by research assistants (see exercise session recording template attached). Monitored Intensity: HR (continuously during), S-RPE (immediately post session) Progressive Overload: Participants will be encouraged to increase the weights lifted during a work period when they can complete > 10 reps in the work period and remain at an RPE <7/10. Participants will be encouraged to increase this weight by approximately 5-10% (or at the discretion of the instructor) the next time that exercise is performed to achieve a rep range of 10 and RPE =7/RPE. Participants will be encouraged to increase distance achieved on ergometers while maintain an RPE =7/ 10. Regression: Participants will be encouraged to decrease the weights lifted during a work period when they are unable to complete 10 reps in the work period. If a participant is observed to be working to fatigue or exhaustion, or with inappropriate technique instructors will advise the participant to reduce either: - the external load (i.e., weights, ergometer resistance) - the reps completed (while remaining in the prescribed 10 rep range) - tempo at which they are performing the exercise - difficulty of the exercise (e.g., push up on toes may be regressed to kneeling push up) Modifications/ scaling: All exercises will be pre-prescribed with scaled alternatives available to suit varying abilities of participants and promote appropriate level of exercise intensity (e.g., kneeling push up, push up on toes, decline push up). Instructors will explain all alternatives when delivering the session overview and participants will be free to choose their starting point. Instructors may then encourage participants to progress or regress these alternatives based on the above progression/ regression methods. In the event that a participant is unable to perform an exercise, instructors will modify the exercise based on pre-prescribed modifications to the program. Instructors will be provided with this information when they receive each training program. Instructors will record events of modification with the participants’ training volume-load diary for the session. Supervision: All training sessions will be completely supervised by qualified exercise professionals (i.e., ESSA AES, Personal Trainers). Third year sport and exercise science students undergoing their placement will assist in session instruction and training volume-load recording. Sessions will be performed in small groups of 3-8 participants (i.e., 1 research assistant: maximum 8 participants). Encouragement/ motivation strategies: Instructors will frequently use phrases such as “great work”, “keep it up”, among other positive phrases. These strategies will be anchored in instructors in a familiarisation session with the research student (TS) to ensure standardisation. Exercise technique: Appropriate exercise technique will be explained by instructors during the familiarisation sessions (baseline testing) and each time a novel exercise is introduced. Instructors will be educated on appropriate exercise technique in a familiarisation session with the research student (TS) to ensure standardisation. Training location (physical environment): All training locations are indoor, weather protected facilities. All locations will have access to the same training equipment to ensure standardisation across locations. Music: All training sessions will play background music >170bpm via a speaker. Participants will perform 3 acute exercise sessions as part of baseline and post-training testing (HIMT, aerobic, resistance sessions). These sessions at baseline will serve as familiarisation sessions for exercise technique, equipment and intensity. Participants will undergo an anchoring exercise to familiarise themselves with S-RPE during these sessions. Participants will be informed about the principles of progressive overload and will be encouraged to gradually increase aerobic and resistance training loads throughout the program while maintaining and RPE = 7/10 (i.e. high-intensity). Who provided: Training sessions will be designed by ESSA accredited exercise scientists (AES) (in collaboration with a Personal Trainer with extensive experience prescribing and delivering CT). Training sessions will be supervised by ESSA AES, Personal trainers and trained instructors (third year Sport and Exercise Science undergraduate students) to ensure ongoing safety. Initial sessions will be supervised by the Principle Investigator and Research Student to ensure that all sessions are delivered to a consistent standard, thereafter trained instructors (third year undergraduate students) will assist in exercise session delivery. How well: Adherence to the intervention will be objectively measured via attendance sheets by the instructors at each training session. Compliance to high-intensity exercise will be calculated according to the % of time spent at or above high-intensity of effort as defined by American College of Sports Medicine (ACSM).