Promoting Health: Interval vs Steady Running vs Strength Training

The optimum physical exercise regimen for promoting health is a key public health issue.  Aerobic exercise can be obtained via running either using a steady pace or an interval-based approach.  Interval approaches typically includes high intensity exercise over shorter bursts of time.  Additionally, strength training provides a variety of health benefits and it’s role compared to aerobic exercise is unclear.

A Danish study was designed and recently published to compare the health benefits of interval training, prolonged steady paced running and strength training.  The key elements of the three interventions were:

• Interval training: 5 minute warm-up followed by 5 two minute intervals at near-maximal running with heart rate above 95% maximum (3 times per week)—total exercise time over 12 weeks approximately 480 minutes
• Steady running: one hour of continuous running three times per at 80% of maximum heart rate—total exercise time over 12 weeks 1800 minutes
• Strength training: progressive heavy-resistance strength training primarily in lower extremities for one hour twice a week—total exercise time over twelve weeks 1500 minutes

Subjects participated in their respective programs for twelve weeks and had a variety of baseline performance, physiologic and lab measures collected.  The main findings showing differences between the groups were:

• Maximum oxygen uptake improvement better in interval group than other two groups
• HDL to total cholesterol improved in the steady running group, remained the same in the interval group and tended to worsen in the strength training group
• Blood glucose (fasting and two hours after glucose load) improved in both running groups but not the strength training group
• Body weight/body fat/muscle mass: Only the steady running group decreased body weight and fat percentage, strength group increased weight, increased lean body mass 

This study helps understand the relative contribution to health promotion for a variety of exercise programs.  Interval training provides the most bang for the buck in increasing oxygen uptake and in glucose metabolism.  Steady running seems superior to other techniques for weight loss and cholesterol reduction.  Strength training alone has limited health promotion benefits primarily in the development of lean body mass.

Since the health benefits of the three types of training studied in the experiment are complementary, it seems reasonable to consider a workout routine using all three types.  Although combining the three would lead to a significant time demand that many are unable to accommodate.  A good study is needed that answers the following question: “Given one hour to exercise, what is the optimum combination of steady running, interval training and strength training?”

Photo of fish from Oklahoma Aquarium (modified using psychedelic mode in iPad Photogene app) courtesy of Yates photography.

Nybo L, Sundstrup E, Jakobsen MD, Mohr M, Hornstrup T, Simonsen L, Bülow J, Randers MB, Nielsen JJ, Aagaard P, & Krustrup P (2010). High-Intensity Training Vs. Traditional Exercise Interventions for Promoting Health. Medicine and science in sports and exercise PMID: 20195181