Related Experiment Video
Updated: Apr 11, 2026
Non-invasive Assessments of Subjective and Objective Recovery Characteristics Following an Exhaustive Jump Protocol
Published on: June 8, 2017
Oral Rehydration Improved Exercise Performance and Decreased Core Temperature and Heartrate Compared With Intravenous
Yasuki Sekiguchi1, Alan T Ky1, Courteney L Benjamin2
1Sports Performance Laboratory, Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, Texas.
Background:
The purpose of this study was to examine the effect of oral versus intravenous (IV) rehydration during exercise in the heat on exercise performance and physiological responses.
Hypothesis:
Oral rehydration will lead to better performance and physiological outcomes.
Study Design:
Cross-over study.
Level Of Evidence:
Level 2.
Methods:
A total of recreational active men (age, 29 ± 12 years; peak oxygen consumption [VO2peak], 49.8 ± 6.6 ml kg-1 min-1) performed 90 minutes of cycling exercise at 55% watts at VO2peak (WVO2peak) followed by a 12-km time trial in the heat (34.9 ± 0.6°C; 30.3 ± 0.9%; wind speed, 3.4 m sec-1). Two experimental trials were performed in random order: (1) drank 25 ml of water every 5 minutes (ORAL) and (2) 25 ml of isotonic saline infused intravenously every 5 minutes (IV). Rectal temperature (Trec) and thirst sensation were measured every 5 minutes. Urine specific gravity (USG) and body mass loss were measured before and after trials. Changes (Δ) were calculated based on the resting value for each trial.
Results:
Participants started both trials euhydrated (USG < 1.020), and no differences were found in hydration status between ORAL and IV after trials (USG:ORAL, 1.012 ± 0.006; P = 0.14; IV, 1.013 ± 0.007; body mass loss: ORAL, 2.4 ± 0.8%; IV, 2.3 ± 0.5%, P = 0.68). Thirst levels were higher in IV than ORAL from 20 to 50 minutes (P = 0.03 to 0.05) and after 65 minutes throughout 90 minutes of cycling exercise and the 12-km time trial (P < 0.001 to 0.04). ΔTrec was also significantly higher in IV after 20 minutes throughout 90 minutes of cycling exercise and a 12-km time trial (P = 0.003 to 0.04). The time trial was significantly faster in ORAL (17.7 ± 4.6 minutes) compared with IV (19.6 ± 6.2 minutes, P = 0.05).
Conclusion:
Oral rehydration enhances exercise performance and decreases Trec and heartrate compared with IV rehydration.
Clinical Relevance:
Oral rehydration might have more benefits than IV in exercise performance and physiological response.
More Related Videos
08:22Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise
Published on: October 7, 2015
10:21Evaluation of Hydration Status by Bioelectrical Impedance Vector Analysis in Patients with Ischemic Heart Disease Undergoing Exercise Stress Test
Published on: September 22, 2023
Related Concept Videos
01:29Strength and Heat of Hydration
The heat of hydration for each cement compound is significant; for instance, tricalcium aluminate (C3A) and...
01:20Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
01:17Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be...
01:25Regulation of Water Intake
01:27Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
01:29Decreased Body Temperature