Exercise as it relates to Disease/Stairclimbing, is it enough for fitness and health in young, inactive women?

What is the background to this research?
Physical inactivity is now considered the fourth largest risk factor for mortality (death) worldwide. Physical inactivity also accounts for 10% of strokes and 20% of cardiovascular disease in developed countries and increases the risk of other chronic diseases including Type 2 diabetes, obesity, breast and colon cancer. These diseases are becoming more common and the associated health care costs are rising dramatically. It is estimated that in the USA the health costs associated with obesity alone will be in the range of US$860 to $950 billion pa by 2030. Despite this, it is estimated that 21% of people worldwide are physically inactive. Doing 150 to 300 minutes of medium physical exercise per week and being physical active most days are the Australian recommended guidelines for physical activity.

Where is the research from?
The research ‘Training effects of short bouts of stair climbing on cardiorespiratory fitness, blood lipids, and homocynsteine in sedentary young women’ was undertaken in Belfast, Northern Ireland by the University of Ulster and The Queen’s University of Belfast, and was published in 2005 in the British Journal of Sports Medicine (BJSM). The BSJM is a reputable journal that publishes sport and exercise related original research and commentary, and is associated with 19 sports medicine and physiotherapy societies. The study was peer reviewed by two external reviewers prior to publication and has been cited over 120 times.

What kind of research was this?
The research was an exercise trial, with the participants randomly allocated into two groups – a control group that didn’t change their sedentary habits and the active group that did the stair climbing program. This type of study is called a randomised, controlled exercise trial. The study could have been improved by increasing the number of participants and the use of more precise instruments for the measurement of some of the factors, e.g. to detect variance.

What did the research involve?
Fifteen young (average 18 years old) sedentary but otherwise healthy women were involved in the study. The eight women in the active group undertook an eight week (5 day per week) stair climbing exercise program. Each set of stair climbing was a flight of 199 steps (33m vertical displacement). The active group started doing one set of stairs each day and this was increased every two weeks (by one set). By weeks seven and eight they were doing five sets a day. The stair climbing could be done any time during the day (with each set taking about 2 minutes) and each set of stair climbing was separated by at least one hour. The active group climbed at a ‘comfortable but brisk rate’ (90 steps per minute), and descended at their own pace. The participants fitness and a number of health indicators (see Table 1) were measured before and after the trial. The results for the control and the active groups were compared to determine the effectiveness of the stair climbing program.

What were the basic results?
The stair climbing resulted in a significant increase in fitness and reduction in bad cholesterol' (Low Density Lipoprotein (LDL-C)). Fitness was measured using VO2max which is the gold standard for measuring aerobic or cardiorespiratory fitness and this increased by 17%. Interestingly, although this increase was statistically significant it only increased the 'active group's VO2max up to the level of the control group, because they started with a lower level of fitness. Repeating the study with more participants would be help confirm and give more confidence in the study's findings. Bad cholesterol in the active group decreased by 7.7%. A number of other health indicators were measured, but there was no significant change in these.

Table 1: Summary of results of stair climbing trial

Other parameters measured that did not change significantly with the stair climbing included: Body Mass Index (BMI), Total Cholesterol, Triglycerides (fats), and good cholesterol (High Density Lipoprotein).

How did the researchers interpret the results?
Sedentary young women can increase their cardiorespiratory fitness and reduce their cardiovascular risk factors by undertaking as little as 11 minutes of stair climbing, five days per week. The researchers claimed the increase in fitness achieved by the women in just 8 weeks should lessen their risk of death by about 20%. The researchers also suggested stair climbing was a more efficient way to improve fitness than walking, claiming that walking 36 minutes a day for 24 weeks was needed to achieve the same increase in fitness. Given the small number of participants and the limited number of factors measured these claims may be difficult to substantiate.

What conclusions should be taken away from this message?
The research suggests that stair climbing is an effective way to increase fitness and decrease bad cholesterol with only a small amount of exercise because of its intensity. Incorporating stair climbing into an exercise program certainly has potential to help improve fitness and health for many people. A big advantage in stair climbing is its low cost, it can be done at any time, it is readily accessible, can be done alone or in a group, and requires no special equipment. (It is noted that the stairs used in this study were similar to those in most commercial locations).

What are the implications of this research?
Stair climbing if appropriately promoted, is likely to appeal to a wide range of people who may be missed by traditional fitness promotion strategies. Participants can expect that stair climbing will help them improve their fitness and reduce their cardiovascular risk, as it provides a combined aerobic exercise and non-traditional form of resistance training. It could be expected that stair climbing could reduce bad cholesterol (LDL) and increase good cholesterol (HDL). The study does not provide any evidence to suggest that including stair climbing in a physical activity program justifies reducing exercise below the Australian recommended guidelines of 150 to 300 minutes of exercise per week.