NCT03101215

Brief Summary

Phosphorus is a widely used sport supplement. Most athletes who use it follow a phosphorus loading approach which consists of a weeklong phosphorus intake of 3-4 gr per day for optimal effect. The ergogenic potential of phosphorus is believed to be related to several factors including its ability to a) enhance ATP availability for energy expenditure and b) increase plasma content of 2.3-DPG (2.3-disphosphoglycerate) that is known to reduce oxygen affinity to hemoglobin and consequently enhances its release in the exercising tissue. Additionally, phosphorus was reported to increase peripheral glucose uptake and thus glycogenesis and glycogen storage. We have recently observed that the peripheral glucose uptake was stimulated by co-ingestion of phosphorus with meal, while pre ingestion failed to do so. Thus it is reasonable to postulate that phosphorus co-ingestion with meal improves ergogenesis through enhancing glycogen storage. The aim of this experiment is to investigate whether acute phosphate supplementation of a glucose load is responsible for the performance enhancement. This may help in explaining the controversies surrounding the impact of phosphorus on performance. A cross over study will be conducted on water polo players. In brief, overnight fasted subjects, will be given glucose load with or without phosphorus. Three hours later their performance will be measured using an ergometer cycling machine.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
17

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Mar 2017

Geographic Reach
1 country

1 active site

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

March 24, 2017

Completed
Same day until next milestone

Study Start

First participant enrolled

March 24, 2017

Completed
12 days until next milestone

First Posted

Study publicly available on registry

April 5, 2017

Completed
12 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 24, 2018

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 24, 2018

Completed
Last Updated

April 5, 2017

Status Verified

April 1, 2017

Enrollment Period

1 year

First QC Date

March 24, 2017

Last Update Submit

April 4, 2017

Conditions

Energy Expenditure

Outcome Measures

Primary Outcomes (1)

  • workload or performance enhancement or METs

    power (watt) and time to exhaustion

    up to 40 min

Study Arms (2)

Placebo

PLACEBO COMPARATOR

glucose drink (100g) with placebo tablets

Dietary Supplement: phosphorus

phosphorus

ACTIVE COMPARATOR

Glucose drink (100g) with phosphorus tablets (400 mg of phosphorus)

Dietary Supplement: phosphorus

Interventions

phosphorusDIETARY_SUPPLEMENT

adding of phosphorus to high carbohydrate meal

Placebophosphorus

Eligibility Criteria

Age18 Years - 25 Years
Sexmale(Gender-based eligibility)
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • water polo player

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

American University of Beirut

Beirut, Lebanon

RECRUITING

Related Publications (13)

  • Buck CL, Wallman KE, Dawson B, Guelfi KJ. Sodium phosphate as an ergogenic aid. Sports Med. 2013 Jun;43(6):425-35. doi: 10.1007/s40279-013-0042-0.

    PMID: 23568374BACKGROUND

  • Chasiotis D. Role of cyclic AMP and inorganic phosphate in the regulation of muscle glycogenolysis during exercise. Med Sci Sports Exerc. 1988 Dec;20(6):545-50.

    PMID: 2853269BACKGROUND

  • Czuba M, Zajac A, Poprzecki S, Cholewa J, Woska S. Effects of Sodium Phosphate Loading on Aerobic Power and Capacity in off Road Cyclists. J Sports Sci Med. 2009 Dec 1;8(4):591-9. eCollection 2009.

    PMID: 24149601BACKGROUND

  • Di Caprio G, Stokes C, Higgins JM, Schonbrun E. Single-cell measurement of red blood cell oxygen affinity. Proc Natl Acad Sci U S A. 2015 Aug 11;112(32):9984-9. doi: 10.1073/pnas.1509252112. Epub 2015 Jul 27.

    PMID: 26216973BACKGROUND

  • Finta KM, Rocchini AP, Moorehead C, Key J, Katch V. Urine sodium excretion in response to an oral glucose tolerance test in obese and nonobese adolescents. Pediatrics. 1992 Sep;90(3):442-6.

    PMID: 1518704BACKGROUND

  • Folland JP, Stern R, Brickley G. Sodium phosphate loading improves laboratory cycling time-trial performance in trained cyclists. J Sci Med Sport. 2008 Sep;11(5):464-8. doi: 10.1016/j.jsams.2007.04.004. Epub 2007 Jun 14.

    PMID: 17569583BACKGROUND

  • Galloway SD, Tremblay MS, Sexsmith JR, Roberts CJ. The effects of acute phosphate supplementation in subjects of different aerobic fitness levels. Eur J Appl Physiol Occup Physiol. 1996;72(3):224-30. doi: 10.1007/BF00838643.

    PMID: 8820890BACKGROUND

  • Khattab M, Abi-Rashed C, Ghattas H, Hlais S, Obeid O. Phosphorus ingestion improves oral glucose tolerance of healthy male subjects: a crossover experiment. Nutr J. 2015 Oct 29;14:112. doi: 10.1186/s12937-015-0101-5.

    PMID: 26514124BACKGROUND

  • Kopec BJ, Dawson BT, Buck C, Wallman KE. Effects of sodium phosphate and caffeine ingestion on repeated-sprint ability in male athletes. J Sci Med Sport. 2016 Mar;19(3):272-276. doi: 10.1016/j.jsams.2015.04.001. Epub 2015 Apr 24.

    PMID: 25953613BACKGROUND

  • Lichtman MA, Miller DR, Cohen J, Waterhouse C. Reduced red cell glycolysis, 2, 3-diphosphoglycerate and adenosine triphosphate concentration, and increased hemoglobin-oxygen affinity caused by hypophosphatemia. Ann Intern Med. 1971 Apr;74(4):562-8. doi: 10.7326/0003-4819-74-4-562. No abstract available.

    PMID: 4994546BACKGROUND

  • Rauch HG, St Clair Gibson A, Lambert EV, Noakes TD. A signalling role for muscle glycogen in the regulation of pace during prolonged exercise. Br J Sports Med. 2005 Jan;39(1):34-8. doi: 10.1136/bjsm.2003.010645.

    PMID: 15618337BACKGROUND

  • Xie W, Tran TL, Finegood DT, van de Werve G. Dietary P(i) deprivation in rats affects liver cAMP, glycogen, key steps of gluconeogenesis and glucose production. Biochem J. 2000 Nov 15;352 Pt 1(Pt 1):227-32.

    PMID: 11062077BACKGROUND

  • Elhusseini R, Fares EJ, Obeid O. Phosphorus supplementation raised the heart rate of male water polo players during a randomised graded dryland exercise test. BMJ Open Sport Exerc Med. 2020 Apr 8;6(1):e000714. doi: 10.1136/bmjsem-2019-000714. eCollection 2020.

    PMID: 32405431DERIVED

MeSH Terms

Interventions

Phosphorus

Intervention Hierarchy (Ancestors)

ElementsInorganic Chemicals

Study Officials

  • omar obeid, PhD

    American University of Beirut Medical Center

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Omar Obeid, PhD

CONTACT

00961 1 350000oo01@aub.edu.lb

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

March 24, 2017

First Posted

April 5, 2017

Study Start

March 24, 2017

Primary Completion

March 24, 2018

Study Completion

March 24, 2018

Last Updated

April 5, 2017

Record last verified: 2017-04

Data Sharing

IPD Sharing
Will not share

Locations

LE(1)