“Milkshaking” horses — the practice of giving them a baking soda concoction — is a risky exercise that does not improve performance, researchers in Australia have concluded.
Sodium bicarbonate “milkshakes” have been used as a supposed performance-enhancing substance in horses in the hours before exercise since the late 1980s.
“Although sodium bicarbonate administration to racehorses 24 hours before racing is a banned practice in most racing industries, whether or not it improves running performance in racehorses is currently unclear,” Joshua Denham and Adam Hulme noted in the Journal of Equine Veterinary Science.
Denham, a lecturer in exercise science at RMIT University in Melbourne, and Adam Hulme, a research fellow at the University of the Sunshine Coast, set out to review available scientific evidence on the practice to learn if it improved running performance in trained Standardbreds and Thoroughbreds.
Denham and Hulme noted that sodium bicarbonate loading is commonly achieved using a tube via the nose to enter the stomach.
“Those in the industry refer to sodium bicarbonate by the lay term, ‘milkshake’.
“Although the administration of ‘milkshakes’ to racehorses within 24 hours of racing violates the rules, and despite regular race-day screening by governing officials, it remains an issue in modern horseracing.
“The practice can also be distressing to the animal and cause serious harm if not performed correctly.”
While minor side effects include digestive upsets and lacerations to the nasopharyngeal structures from the tube, there can be much more serious consequences such as death when the tube erroneously enters the trachea rather than the esophagus, flooding the lungs with a concentrated solution.
For their review, the pair conducted a comprehensive search for relevant studies that met their criteria.
They found seven randomized controlled trials suitable for inclusion comprising experimental exercise-based trials involving 74 horses.
The results indicated that sodium bicarbonate administration 2.5 to 5 hours before a standardized treadmill test to exhaustion, or a simulated time-trial, did not influence running performance.
“There is high-quality evidence to suggest that sodium bicarbonate administration does not improve running performance in trained Standardbred or Thoroughbred horses,” they concluded.
Discussing their findings, the authors noted that despite the risk to racehorses, and the practice being banned 24 hours before racing in most countries, some trainers continued to administer milkshakes for a perceived performance edge.
They said acute sodium bicarbonate administration did not improve running performance measured in time to exhaustion in treadmill exercise trials. In fact, analysis indicated a very small negative effect. Nor did it influence running performance as judged by a simulated race.
“The results from the present study directly oppose the common beliefs that milkshakes enhance running performance in racehorses,” they said. “The authors cannot think of another reason why individuals would administer milkshakes to their racehorses if not for the potential performance benefits, although not all human beliefs are justified scientifically.”
A Systematic Review and Meta-analysis on Sodium Bicarbonate Administration and Equine Running Performance: Is it Time to Stop Horsing Around With Baking Soda?
Joshua Denham and Adam Hulme
Journal of Equine Veterinary Science Volume 95, December 2020, 103281 https://doi.org/10.1016/j.jevs.2020.103281
The review can be read here.