TITLE:
The Addition of High Intensity Interval Training Reduces Cardiovascular Disease Risk Factors and Enhances Strength in Active, Healthy Adults
AUTHORS:
Jinger S. Gottschall, Christopher M. Bopp, Bryce Hastings
KEYWORDS:
Physical Fitness Guidelines, Group Exercise, Cholesterol, Triglycerides, Body Mass
JOURNAL NAME:
Open Journal of Preventive Medicine,
Vol.4 No.5,
May
14,
2014
ABSTRACT:
The guidelines for
cardiovascular exercise intensity are not clear with respect to the optimal
training protocols to reduce cardiovascular disease risk (CVD) as well as to
enhance strength. At this time, it is impossible to deduce the independent
effects of vigorous-intensity exercise from past studies as the volume of
either physical activity duration or energy expended differed in comparison to
moderate-intensity exercise. Our goal was to augment the literature focused on
the potential benefits of high intensity training with novel methodology that
includes trained adults in a group fitness environment. Vigorous intensity
training may be a critical component of the physical activity prescription if
active adults demonstrate decreases in CVD risk factors and increases in
strength. We hypothesize that a 6-week high intensity group fitness
intervention will produce beneficial effects on CVD risk factors by reducing
body mass, total cholesterol, LDL-C, triglyceride concentration, and by
enhancing lean body mass percentage, HDL-C, glucose tolerance, and maximal
oxygen consumption as well as both upper and lower body strength. Eighty-four
healthy adults, 50 women and 34 men, completed the 6-week intervention. Participants
were randomly assigned to one of two groups; the first was a high intensity
interval-training (GRIT) program, while the second was a moderate
intensity-training (FIT) program. All participants completed 5 hours of fitness
classes per week. We collected musculoskeletal and physiological data at the
start and finish of the study. In support of our hypotheses, the GRIT group
significantly reduced body mass, triglyceride concentration and enhanced lean
body percentage, glucose tolerance, and maximal oxygen consumption in addition
to all of the strength measures. These results illustrate a novel finding that
individuals who already participate in the recommended physical activity
guidelines can improve their health, fitness and strength with the addition of
2, 30-minute sessions of high intensity interval training per week.