(RxWiki News) With the busy schedules many Americans have adopted, little time may be left over to get fit. But five minutes may be all that's needed to improve their health.
Four minutes of vigorous activity three times a week improved blood pressure and physical fitness in otherwise healthy, inactive men, according to a recently published study.
The quick exercise training program can be mixed into the busiest of schedules and adapted into programs to improve the public's health, the researchers wrote.
"Short on time? Get active for four minutes!"
Researchers led by Arnt Erik Tjønna, a postdoctoral fellow at the Norwegian University of Science and Technology's KG Jebsen Centre for Exercise in Medicine/Cardiac Exercise Research Group, investigated the optimal exercise intensity and duration needed to be fit.
The researchers measured the VO2max in 26 inactive but healthy men after 10 weeks of fitness training. VO2max is the total amount of oxygen that can be consumed during exercise and is used to measure a person's fitness level.
The study participants were between 35 and 45 years of age with a body mass index (BMI) between 25 and 30. BMI is a measure of a person's body weight and height. The men had not exercised for at least two years since the start of the study.
Half of the participants were randomly assigned to do a single 4-minute bout of exercise three times a week.
The rest were assigned to do four 4-minute bouts of exercise three times a week with a 3-minute break to recover in between each bout.
Both groups trained by walking, running or jogging on an inclined treadmill, including warm up and cool down time. In total, the first group exercised 19 minutes at each session and the second group exercised for 40 minutes.
A single bout of exercise increased participants' VO2max to a similar extent as those who had multiple exercise bouts, the researchers found.
As a result, participants could work out harder and their blood pressure and fasting glucose levels improved. A fasting glucose test measures the amount of sugar in the blood after not eating for at least eight hours and is a measure used to check for diabetes.
The single bout exercise group and multiple bout exercise group increased their VO2max by 10 percent and 13 percent, respectively.
Only participants in the multiple bout group saw improvements in their body fat, total cholesterol and LDL cholesterol ("bad" cholesterol).
"Our study demonstrated that slightly overweight and healthy individuals only required brief duration bouts of exercise with good effort three times a week to produce large increases in VO2max and work economy and reduce blood pressure and fasting glucose levels," the researchers wrote in their report.
Jack Newman, a High Performance Coach and dailyRx Contributing Expert, says that some elite level athletes can reap similar benefits when exercising hard for short periods of time.
"Elite level athletes can train up to 30 hours per week, usually two sessions per day broken up by at least a four hour recovery period," Newman said.
"However, some elite level athletes train for much less time at a higher intensity level and achieve similar results, which parallels the results of this study."
The authors noted that their study had a small number of participants and did not look at a more diverse group of individuals.
Future research should include a wider variety of participants and look at how the short bouts of exercise affect individuals over a longer period, the researchers wrote.
This study was published online May 29 in the journal PLOS One. No conflicts of interest were reported.
The research was funded by the K.G Jebsen Foundation, Norwegian Council of Cardiovascular Disease, Norwegian Research Council and the Cardiovascular and Medical Research at St Olav's University Hospital in Trondheim, Norway, and the Eckbos Foundation in Oslo, Norway.