ACU Research Study: 12-wk Exercise and High Protein Diet Study

What is the project about?

Exercise is well known to induce multiple physical and psychological benefits, although the nature of these benefits is dependent on the type of exercise performed. For instance, resistance training can increase muscle strength and mass, while endurance exercise can enhance the ability and efficiency to use energy so that exercise can be performed at higher intensities or longer durations.

Many individuals who undertake exercise, particularly those involved in team sports, perform a combination of resistance and endurance exercise so that all the physical benefits of exercise can be attained. However, previous research has established that the gains in muscle strength and mass with resistance exercise can be reduced when resistance exercise is performed concurrently with endurance exercise. The mechanisms responsible for this reduced response are not completely understood, but may be related to a combination of factors including fatigue, inadequate exercise intensity and/ or duration, and poor diet to facilitate muscle growth. In this regard, it is well established that protein ingestion can enhance muscle growth responses with resistance exercise. Whether protein can similarly enhance muscle growth following combined resistance and endurance exercise is not known. Accordingly, the aims of this research project are to:

1. Determine whether a high protein diet can ‘rescue’ the loss of muscle growth following 12 weeks of combined resistance and endurance exercise compared to resistance exercise only.

2. Characterise the effects of 12 weeks of combined resistance and resistance and endurance exercise on several performance tests measuring strength and power, and compare these responses to resistance or endurance exercise performed in isolation.

------------------------------------------------------------

Who is undertaking the project?

This project is principally being conducted by Dr. Donny Camera with the assistance of his PhD student, Mr. Bobby Shamim. Bobby is a PhD student at the Australian Catholic University (ACU) and this research project will form part of his thesis. Dr. Camera is a research fellow within Exercise and Nutrition Research Group at ACU and has ten years’ research experience conducting exercise and nutrition studies. Professor John Hawley is the Head of the Exercise and Nutrition Research Group at ACU and possesses over 30 years’ research experience. Ms Brooke Devlin is an Accredited Practising Dietitian (APD) and the research dietitian with Exercise and Nutrition Group at ACU. Dr. Ryan Timmins is a Lecturer within the School of Exercise Science at ACU and has recently graduated from his PhD. Mr. Paul Tofari is a lecturer within the School of Exercise Sciences and will co-ordinate all exercise performance testing. The project has been approved by the ACU Human Research Ethics Committee and is supported and funded by a Collaborative Research Network (CRN) project grant awarded to Dr. Camera.

------------------------------------------------------------

What will I be asked to do?

If you are interested in participating in the study and meet the selection criteria (are healthy, aged 18-30 years, have a Body Mass Index (BMI) of 18.5-29, and recreationally active), you will be required to complete and sign a consent form, a cardiovascular risk factor questionnaire and a muscle biopsy information form for clearance into preliminary strength and performance tests, and the subsequent experimental intervention. It is desirable that your local doctor be advised of your decision to participate in this research project. Factors that may exclude you from taking part in this study include: not meeting selection study inclusion criteria or an inability to consent to the study. Certain medications may also prevent inclusion in the study and the study doctor will advise of this.

------------------------------------------------------------

Dietary Intervention

For the duration of the 12-week exercise and nutrition intervention, participants will consume a ‘high’ protein diet. A diet is considering high in protein if it consumed above the recommended daily intake of 0.8g/kg/day. In this study, daily protein intake will be set at 2 g/kg/day, with a recommended total daily energy intake of 30 – 40 kcal/kg/day. This level of protein consumption is completely safe with similar, and in many cases, higher quantities used within the research field.

Individual diet counselling as well as personal food and recipe plans will be provided by the study dietician Ms. Brooke Devlin on a weekly basis for the first three weeks and then fortnightly to the end of the study. Participants will log their food intake using the Easy Diet Diary™ mobile phone App or manually through a ‘food diary’ which will be co-ordinated by Ms. Devlin. Food preferences and allergies will be discussed at an initial consultation meeting.

------------------------------------------------------------

Exercise Training Program

For the duration of the 12-week exercise and nutrition intervention, participants will undertake exercise training in one of three groups listed below. Participants will be randomly and equally assigned to one of the groups following preliminary testing and all 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

Group 1: Resistance Exercise Only with High Protein Diet
Participants in Group 1 will consume a ‘high protein’ diet as described above and perform only resistance exercise three times per week for the duration of the 12-wk training period. Resistance exercise will progressively increase in weight to account for increases in muscle size and strength throughout the program.
The resistance exercise protocol will consist of a whole-body routine including the following types of exercises: chest press, lat pulldown, rows, leg extension, leg press, shoulder press and lunges. The training protocol will be broken down into the following phases:
1) Phase 1 – Familiarization (Week 1): Sessions in this period will introduce main movements and exercises.
2) Phase 2 – Hypertrophy (Weeks 2-6): Sessions in this period will focus primarily on building muscle mass through higher volume of repetitions per session. Load will increase in a linear progression throughout this phase.
3) Phase 3 – Power (Week 7): Sessions in this phase of training will act as a ‘de-loading’ period and aim to improve muscle power in primary movements.
4) Phase 4 – Strength (Weeks 8-10): Sessions in this phase will focus on strength development and consist of a lower volume of repetitions paired with heavier weights. A linear increase in load will also be used during this phase.
5) Phase 5 – Peaking (Weeks 11-12): Sessions in this phase will focus solely on peaking the neuromuscular system and preparing for the main movements performed during the final strength testing.

Group 2: Endurance Exercise Only with High Protein Diet
Participants in Group 2 will consume a ‘high protein’ diet as described above and perform only endurance-based exercise three times per week for the duration of the 12-wk training period.

Endurance exercise will consist of variety of diverse exercise sessions including:
• 30-45 minutes of cycling on a stationary ergometer at approximately 60-85% of VO2peak capacity at a speed of approximately 60-70 rpm
• High-intensity interval training involving 5 mins of cycling at approximately 60-85% of each individual’s pre-determined VO2peak capacity with short recovery periods.
• Sprint interval training involving <60 seconds of cycling at approximately 100% of each individual’s pre-determined VO2peak capacity with short recovery periods.

Group 3: Combined Resistance and Endurance Exercise with High Protein Diet
Participants in Group 3 will consume a ‘high protein’ diet as described above and will perform combined resistance and endurance exercise three times per week for the duration of the 12-week training period. The concurrent training program will incorporate the same resistance and endurance exercise protocols mentioned in Group 1 and Group 2, respectively, in a single session.

------------------------------------------------------------

If you feel that you meet the study criteria and are keen to get involved, or would like to know more about the study, please do not hesitate to contact us here on Facebook or by phone/email!