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Trial registered on ANZCTR


Registration number
ACTRN12616001466437
Ethics application status
Approved
Date submitted
13/10/2016
Date registered
20/10/2016
Date last updated
3/11/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Zinc metabolism during exercise and recovery
Scientific title
Zinc metabolism during exercise and recovery in healthy adults
Secondary ID [1] 290313 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
nutrition 300574 0
zinc metabolism 300575 0
exercise 300576 0
Condition category
Condition code
Diet and Nutrition 300429 300429 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will complete both the exercise and resting session. The order of the two sessions will be randomised. The washout period will be between 3 to 5 weeks.

The exercise intervention session will be a continuous progressive protocol to maximal exercise capacity on a cycle ergometer; the typical duration of the exercise session will be 8-12 minutes depending on individual physical fitness. Initially, participants will complete a 3 min warm up period with no resistance. The exercise session starts at a resistance of 100 W (or 75 W for smaller individuals); the resistance will increase by 50 W every 2.5 min until heart rate reach 160 bpm, then the resistance will increase by 25 W every 2.5 min until maximal exercise capacity. Measures, such as blood, will be taken during the exercise and recovery (up to 2 hours after exercise).
Intervention code [1] 296126 0
Lifestyle
Comparator / control treatment
In the resting session, the participant will remain sedentary for 2 hours and 10 minutes. The participant will remain seated in a chair for the entire duration of the session, with the exception of bathroom breaks.
Control group
Active

Outcomes
Primary outcome [1] 299873 0
Serum zinc, unadjusted
Serum zinc, adjusted for haematocrit
Timepoint [1] 299873 0
Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation.

For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.
Secondary outcome [1] 328360 0
Gene expression of zinc transporter (ZIP7)

Gene expression will be measured by Taqman quantitative PCR from blood samples.
Timepoint [1] 328360 0
Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation.

For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.
Secondary outcome [2] 328361 0
Urinary zinc excretion
Timepoint [2] 328361 0
24 h urinary zinc excretion, continuous collection over 24 hours following commencement of the exercise or resting session (exercise group compared to resting)
Secondary outcome [3] 328362 0
Red blood cell zinc
Timepoint [3] 328362 0
Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation.

For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.
Secondary outcome [4] 328487 0
Sex hormones (progesterone and oestrogen) in serum assay
Timepoint [4] 328487 0
Baseline for females
Secondary outcome [5] 328488 0
Inflammatory biomarkers (CRP or AGP) in serum assay
Timepoint [5] 328488 0
Baseline
Secondary outcome [6] 328489 0
Exercise outcomes (VO2max by expired air gas analysis, rate of perceived exertion by Borg RPE scale, heart rate by chest heart rate sensor)
Timepoint [6] 328489 0
Exercise outcomes: before exercise, every 3 minutes during exercise, and immediately upon completion of exercise

Resting outcomes, during first 10 minutes of session
Secondary outcome [7] 328561 0
Gene expression of zinc transporter (ZnT1). Gene expression will be measured by Taqman quantitative PCR from blood samples.
Timepoint [7] 328561 0
Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation.

For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.
Secondary outcome [8] 328562 0
Gene expression of metallothioniein (MT-2A)

Gene expression will be measured by Taqman quantitative PCR from blood samples.
Timepoint [8] 328562 0
Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation.

For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.
Secondary outcome [9] 337556 0
Neopterins in plasma and urine.
Timepoint [9] 337556 0
Plasma: Before, immediately after the exercise session, 30 minutes following exercise cessation, 1 hour following exercise cessation and 2 hours following exercise cessation. For the resting group, 0, 10 min, 40 min, 1h 10 min, 2 h 10 min.

Urine: 24h urine collection on resting and exercise day

Eligibility
Key inclusion criteria
Healthy men (n = 30) and women (n = 30), aged 18-30, will be recruited for the study.
Minimum age
18 Years
Maximum age
30 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Haemoglobin will be measured to exclude volunteers with anaemia. Exclusion criteria include: anaemia, habitual smokers, women who may be pregnant or breastfeeding, women who have amenorrhea or oligomenorrhea, those with a diagnosis of major illness, the use of prescription medication including contraceptive agents and medical contraindication to maximal exercise testing.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 8314 0
New Zealand
State/province [1] 8314 0

Funding & Sponsors
Funding source category [1] 294701 0
University
Name [1] 294701 0
University of Otago
Address [1] 294701 0
Department of Human Nutrition
PO Box 56 Dunedin 9054
New Zealand
Country [1] 294701 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
Department of Human Nutrition
PO Box 56 Dunedin 9054
New Zealand
Country
New Zealand
Secondary sponsor category [1] 293546 0
None
Name [1] 293546 0
Address [1] 293546 0
Country [1] 293546 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296122 0
University of Otago Human Ethics Committee (Health)
Ethics committee address [1] 296122 0
PO Box 56,
Dunedin 9054,
New Zealand
Ethics committee country [1] 296122 0
New Zealand
Date submitted for ethics approval [1] 296122 0
10/10/2016
Approval date [1] 296122 0
17/01/2017
Ethics approval number [1] 296122 0

Summary
Brief summary
In our recent meta-analyses, exercise has been shown to induce changes in serum zinc levels. However, the quantified results are confounded by multiple study limitations, for example failure to adjust for exercise-induced changes in blood volume.
Further, in a previous trial, we observed a significant relationship between habitual physical activity level and zinc transporter gene expression. This suggests that cellular zinc homeostasis may be affected by exercise level, possibly due to exercise adaptations. Therefore, the principal study question is: What is the effect of a maximal cycling exercise bout on markers of zinc homeostasis in healthy men and women?

Healthy men (n = 60) and women (n = 60), aged 18-30, will be recruited. Recruited participants will be randomised into an exercise session (n = 30 men, 30 women) or a resting session (n = 30 men, 30 women). Pre-screening questionnaire and a measurement of hemoglobin will be used to determine eligibility for participation.
Height, weight, body composition (by bioelectrical impedance analysis) and habitual physical activity level will be collected. Dietary intake will be evaluated with a 3-day food record. 24-h urine collection will be taken on the exercise/resting day to measure urinary zinc excretion.
The exercise session will involve a continuous progressive protocol to maximal exercise capacity on a stationary bicycle. Oxygen consumption levels will be measured during the test to obtain level of maximal oxygen consumption (VO2max). Heart rate and rate of perceived exertion will be measured during the test. Blood samples will be collected before exercise, immediately after exercise and at 3 time points during exercise recovery. In the resting session, participants will be sedentary for the blood collection time course. Blood samples will be measured for zinc outcome, gene expressions, haematocrit, sex hormones, inflammatory markers.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 69634 0
Dr Anna Chu
Address 69634 0
Department of Human Nutrition
University of Otago
PO Box 56
Dunedin 9054
New Zealand
Country 69634 0
New Zealand
Phone 69634 0
+64 3 479 7959
Fax 69634 0
Email 69634 0
anna.chu@otago.ac.nz
Contact person for public queries
Name 69635 0
Dr Anna Chu
Address 69635 0
Department of Human Nutrition
University of Otago
PO Box 56
Dunedin 9054
New Zealand
Country 69635 0
New Zealand
Phone 69635 0
+64 3 479 7959
Fax 69635 0
Email 69635 0
anna.chu@otago.ac.nz
Contact person for scientific queries
Name 69636 0
Dr Anna Chu
Address 69636 0
Department of Human Nutrition
University of Otago
PO Box 56
Dunedin 9054
New Zealand
Country 69636 0
New Zealand
Phone 69636 0
+64 3 479 7959
Fax 69636 0
Email 69636 0
anna.chu@otago.ac.nz

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary