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Take part in Nutritional Physiology research

Research in the Nutritional Physiology Laboratory focuses on the effects of nutrition and exercise on muscle metabolism and health. Projects recruiting participants are posted on this page.

How to take part 

If you are interested in taking part in one of the studies below, please first read the inclusion criteria to ensure you are suitable for the study. You can then email the researcher who is running the study for more information or to schedule a screening visit.

Studies currently recruiting participants

Title:

The effect of menstrual cycle phase on muscle protein synthesis in response to exercise and a protein-polyphenol drink in young females.

Researcher Name:

Marianna Apicella

Brief Summary:

Protein and polyphenol supplements are commonly consumed post resistance exercise in order to aid muscle recovery. Both supplements have been shown to be beneficial in isolation, however, there is little known about the effect on recovery of combining the two.

Muscle recovery is related to the ability to build new muscle protein from amino acids (muscle protein synthesis). This response is thought to be impacted in females by hormones that fluctuate across different phases of the menstrual cycle. However, the effect of menstrual cycle phase on muscle protein synthesis during recovery is not known.

Therefore, this present study will assess the impact of menstrual cycle phase and a protein-polyphenol drink consumption on muscle recovery.

Who is eligible:

  • Healthy recreationally active females
  • Aged 18-40 years old
  • BMI between 18.5-30 kg/m2
  • Non-smokers
  • Not currently on any hormonal contraceptives
  • Not allergic to milk or pomegranate

What is involved?

You will visit the Nutritional Physiology research lab (St Luke’s Campus) a total of four visits. You will also need to track your menstrual cycle.

Visit 1 (~2h): Screening and strength testing

  • You will complete a health screening questionnaire and we will determine if you are eligible to take part in the study. If you agree to take part, informed consent will be taken.
  • Your height, weight, blood pressure and body composition will be measured.  
  • You will complete lower body strength testing in one leg using the leg press and leg extension machines.
  • After this visit, you will need to track your menstrual cycle.

Visit 2 (~30mins): Familiarisation visit

You will complete strength testing in one leg using the leg press and leg extension machines.

Visit 3 & 4 (~8h each): Experimental visit

  • You will consume a standardized meal provided by the research team on the evening before each experimental trial visit.
  • You will arrive fasted to the labs.
  • You will be resting in bed in a semi-supine position.  
  • You will undergo a continuous intravenous infusion of an amino acid stable isotope.
  • Repeated blood samples will be taken throughout the day.
  • Muscle samples will also be taken throughout the day, two per leg.
  • Repeated blood flow measurements will be taken throughout the day.
  • You will perform a lower body resistance exercise workout in one leg.
  • You will consume either a protein or a protein-polyphenol drink.

Visit 4 will be exactly the same as visit 3 but this will be completed at a different phase of the menstrual cycle.

Visit 5 (~20 minutes): Blood Sample

  • You will arrive fasted to the labs.
  • You will be resting in bed in a semi-supine position. 
  • A single blood sample will be taken from your elbow.

Compensation allowance:

£250

Title:

The effect of a peat and apple extract on muscle ATP and exercise performance.

Researcher Name:

George Pavis

Brief Summary:

Adenosine triphosphate (ATP) is the sole substance used to fuel muscle contraction. However, the store of ATP in muscle is relatively small. The aim of this study is to test whether a supplement that contains ancient peat and apple extract, which has been shown to increase ATP in blood, will increase ATP in muscle. We will also test whether this leads to improved timetrial performance after an exhaustive bout of cycling.

Who is eligible?

  • Generally active individuals aged 18-40.
  • Anyone not taking prescription medication (apart from oral contraceptive).

What is involved?

A VO2 max test, a familiarisation visit, then two test days at the nutritional physiology labs at St Luke’s Campus.

The test days will include:

  • Muscle, blood and urine sampling.
  • Roughly 2h steady state cycling, designed to cause fatigue.
  • 15 min time trial.
  • Consumption of a novel supplement.

Compensation allowance:

£150

Title:

Does a multi-ingredient caffeine-containing pre-workout supplement enhance cycling time trial performance and subsequent recovery?

Researcher Name:

George Pavis

Brief Summary:

Athletes use ergogenic aids to gain a performance advantage over their competitors. This can come in the form of improving acute performance or enhancing recovery from exercise.

Caffeine has been demonstrated to be an effective ergogenic aid regarding acute improvements in endurance exercise performance. However, there is also emerging evidence that caffeine consumption can also improve recovery from exercise through augmented glycogen resynthesis, with glycogen being one of the primary fuel sources of exercising muscle. Therefore, this study aims to see if a coffee-based caffeine-containing supplement can improve exercise performance and recovery.

Who is eligible?

  • Trained Endurance athletes aged 18-40
  • Habitual caffeine consumers
  • Not currently taking prescription medication

What is involved?

Six visits to the nutritional physiology labs at St Luke’s Campus, with the first being a VO2max test to assess suitability to participate. This is followed by a familiarisation visit and then 4 test days.

Test days will include:

  • Muscle, blood and urine sampling
  • 30 minutes of steady-state cycling followed by a 15 minute time trial
  • Consumption of a supplement
  • Gas analysis throughout each exercise bout

Compensation allowance:

£150

Title:

Effects of vitamin D supplementation on muscle protein synthesis (VIPER)

Researcher Name:

Raquel Revuelta Iniesta and Amy Booth

Brief Summary:

Healthy adults maintain muscle tissue by continuously building up and breaking down muscle proteins throughout the day. Studies have shown that vitamin D is essential for maintaining muscle mass by activating cellular pathways involved in building muscle. Although, various candidate molecules have been identified in animal models, it is not known whether these pathways are activated in humans. Interestingly, animal studies indicate that 20% of Vitamin D is stored in human muscle cells, which may help maintain optimal vitamin D levels during winter in Northern latitudes when there is not much sunlight. We would like to investigate whether vitamin D helps build muscle up following 12 weeks of vitamin D supplementation and if so how this happens.

Who is eligible?

You have been chosen if you are:

  • A healthy adult male or female
  • Between the ages of 18-45 years
  • Do not exercise or do some form of occasional exercise or physical activity

Unfortunately, you will not be able to partake if:

  • You have been abroad to a sunny warm place located below 37°N latitude
  • You have used sunbeds
  • You have taken (or are taking) vitamin D supplements in the last 30 days prior to this study
  • You are allergic to lidocaine and/or cow’s milk protein
  • You are a regular smoker
  • You have been diagnosed with a chronic condition

What is involved?

If you are interested in taking part in the study, there will be several steps to the project. We would ask that you come to the Nutrition and Physiology Research Unit, St Luke's Campus, University of Exeter on three occasions.

Visit 1 will take approximately 90 minutes 

Appointments will be arranged at most convenient time

This visit consist of the following:

  • Show you the facilities and exercise involved in the intervention
  • We will measure your body composition using an Air Displacement Plethysmography (BodPod, Life Measurement, Inc.).
  • We will ask you to complete a few forms: vitamin D food frequency questionnaire (FFQ), a 4 days diet diary and a 4 day activity log (on two occasions)

Visit 2 and 3 will take approximately 8 hours

  • We will provide with a standard meal for you to eat the night before your visits.
  • The next morning you will arrive at the lab after a 10 h overnight fast.
  • We will ask you to lie down on a bed. We will then insert a cannula into a forearm vein. This cannula will be used for an infusion of labelled amino acids.
  • We will insert a second cannula into a hand vein for blood sampling. After the first blood sample has been taken, your hand will be placed in a hot box (~55 °C) to keep it warm. In total, we will take 16 blood samples throughout the day from the same cannula.
  • We will take 4 small muscle samples (muscle biopsy) from your upper leg.
  • 90 minutes after the first biopsy you will be asked to perform an exercise session. This will involve 4 sets of 10 reps leg extension and leg press with all-out effort. There will be a 2 minute rest between sets. Exercise will only be performed in one leg.
  • After completion of the exercise, you will be asked to consume 20g of whey protein bolus
  • In visit 1, you will be given either placebo or vitamin D supplementation to take for the next 12 weeks (one spray shot per day) until your next visit.
  • In visit 3, we will measure your body composition using an Air Displacement Plethysmography (BodPod, Life Measurement, Inc.) as well as all of the above.

Compensation allowance:

£200

Title:

Exploring muscle breakdown during exercise recovery

Researcher Name:

Kiera Wilkinson and George Pavis

Brief Summary:

This study will allow us to explore how muscle responds to heavy exercise. We will characterise rates of muscle protein breakdown and synthesis 24 hours after heavy exercise with a post exercise protein polyphenol or placebo supplementation. This will inform strategies to help people recover from heavy exercise.

Who is eligible?

Men and women, age 18-40 years, recreationally active but not involved in structured resistance/ weight training.

What is involved?

Visit 1:

You will be asked to attend the laboratory on St Luke’s campus (St Luke's Campus) to take some basic measures of height and weight. Then, we will familiarise you with the exercise protocol, so you can get a feel for the study. You will then be given a post exercise protein or placebo supplement to consume every day for 7 days.

Visit 2 (~1hour):

Following 7 days of supplementation, you will come into the laboratory to perform the heavy exercise (10 sets of 30 resisted quadriceps contractions in one leg) and we will give you the supplement and breakfast. We will also give you lunch and dinner to take home with you.

Visit 3 (~8hours):

The morning after visit 2, we will measure muscle soreness upon arrival. Then, we will place a cannula into a forearm vein. This will be to infuse a stable isotope amino acid ‘tracer’. We will also place a cannula into a hand vein to take repeated blood samples. These will be in place for 6 h whilst you rest in bed.

To assess the rate of muscle protein synthesis and breakdown we will take a small muscle biopsy (a small piece of muscle tissue) from your leg. Six muscle biopsies will be taken in total, 3 from one leg and 3 from the other. This muscle biopsy will be done under local anaesthetic and you will likely have mild soreness and bruising but it will not prevent you from performing you general daily activities.

Compensation allowance:

£100

Title:

Assessing the muscle protein synthetic response following the ingestion of a variety of protein rich whole foods compared to an isolated protein source.

Researcher Name:

Freyja Haigh

Brief Summary:

To date, most of the literature investigating the role of dietary protein in muscle growth has focused on isolated protein sources. However, dietary protein is most commonly consumed within a whole food source. Consuming dietary protein within a whole food matrix may additionally stimulate muscle growth. The idea being, there may be other components within food, capable of producing a greater response.

The aim of this study is to assess the effect of consuming a variety of whole food sources, on the stimulation of muscle growth compared to an isolated protein source following a single bout of lower body resistance exercise.

Who is eligible?

  • Males and females, aged 18-40
  • BMI between 18.5 and 30
  • Resistance trained (>6 months (>3x a week))

What is involved?

If you are eligible, you will come to the laboratory on 2 occasions.

Visit 1 (~1.5h)

  • Completion of health screening and informed consent.
  • Anthropometric, blood pressure and body composition measurements will be performed.
  • Test leg muscle strength from a leg extension and leg press exercise to assess 3 RM.
  • Completion of a 3-day food diary to establish habitual dietary intake.

Visit 2 (~9h)

  • Blood and muscle biopsy samples will be taken.
  • Completion of resistance exercise – 3 sets of 10 reps leg press and leg extension.
  • Consumption of a whole food source

Compensation allowance:

£100

Title:

Does combining protein and polyphenol work together to enhance muscle synthesis above that of protein alone?

Researcher Name:

Amy Booth

Brief Summary:

It is widely acknowledged that the consumption of a post-exercise whey protein drink aids recovery. Polyphenols, found in cherries, have been promoted as effective anti-oxidants, anti-inflammatories and nitric oxide mediated blood vessel dilators.

Although, whey protein and cherry polyphenol have been investigated as individual supplements, it is unknown whether they work together to produce an enhanced response to muscle protein synthesis via increased blood flow and transportation of protein to muscles above that of whey protein alone.

Who is eligible?

We are looking for healthy, sedentary to moderately active, 18-40 year old, males and females to take part in this study.

What is involved?

This study involves 2 visits to the Nutritional Physiology lab (St Luke’s Campus)

Visit 1 (~1h): Screening and strength testing

  • Your eligibility will be assessed via a health screening questionnaire. Informed consent will be taken if you agree to take part.
  • You will be asked to complete a 4-day food and activity diary to assess your habitual dietary intake and activity patterns.
  • At least 5 days before the experimental visit (Visit 2) you will complete a strength testing session to determine your 10-rep max in the leg press and leg extension.

Visit 2 (~7.5h): Experimental visit

  • You will arrive fasted to the labs.
  • You will undergo a continuous intravenous infusion of an amino acid stable isotope
  • Repeated blood samples will be taken throughout the day
  • Multiple muscle samples will also be taken throughout the day (x2 per leg)
  • You will perform a lower body resistance exercise workout.
  • Consume a protein or protein and polyphenol post-exercise beverage.

Compensation allowance:

£100