The Effects of Varying Loads and Repetitions on Caloric Expenditure During Traditional Back Squats

Open Access
Barrett, Samuel Thomas
Area of Honors:
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Jinger Gottschall, Thesis Supervisor
  • Steriani Elavsky, Honors Advisor
  • caloric expenditure
  • energy expenditure
  • exercise
  • squats
  • repetitions
  • loads
  • physical activity
  • kinesiology
  • contraction speed
A leading topic of interest in the health-fitness and wellness industry is how to maximize caloric expenditure in the shortest amount of time through physical activity. The goal of this study is to identify a resistance training (RT) protocol that appeals to these two demands through the use of the back squat exercise. A total of 15 subjects between the ages of 18 and 40 participated in four separate exercise protocols in a randomized order. Each protocol performed the same amount of work in the same 4 minute duration using either a 5kg, 10kg, 15kg, or 20kg load at a contraction speed of 1, 2, 3, or 4 seconds respectively. The mean physical activity energy expenditure (PAEE) demonstrated a trend of decreasing as the loading increased from 5kg to 20 kg with a 29.3% difference between the 5kg and 20gk condition values. All of the mean heart rate (HR) recordings exhibited a similar trend of decreasing as loading increased from 5kg to 20kg with the exception of the mean minimum HR (MNHR) measurements in which case the largest value was associated with the 10 kg load as opposed to the 5kg load. The mean values for MNHR indicated an 8.7% difference between the 10kg condition and the 20kg condition while the 5kg condition displayed a 4.9% difference. For the average heart HR (AHR) values, there proved to be a 13.4% difference between the 5kg and 20kg conditions while the maximal HR (MXHR) values showed a 13.8% difference. In conclusion, using a work load that maximizes the total work output as a result of a high capacity for the number of repetitions performed at the fastest rate of contraction will most likely yield the highest PAEE.