Resistance exercise such as lifting weights produces a different pattern of blood vessel responses than aerobic exercise, which may mean that it has specific and important benefits for cardiovascular health, according to a study in the November issue of The Journal of Strength and Conditioning Research, official research journal of the National Strength and Conditioning Association, published by Lippincott Williams & Wilkins a part of Wolters Kluwer Health, Philadelphia.

"Resistance exercise may offer greater benefits from the increases in blood flow to active muscles and could be implemented as companion to an aerobic training regimen," according to the new study, led by Scott R. Collier, PhD, of Appalachian State University, Boone, NC.

The researchers compared vascular responses to two different types of moderate-intensity exercise: a set of eight resistance exercises, three sets of 10 repetitions; and 30 minutes of aerobic cycling. Responses measured included blood vessel widening in response to increased blood flow and arterial stiffness, which are key contributors to cardiovascular health.

Vascular responses to the two types of exercise were significantly different. Resistance exercise produced greater increases in blood flow to the limbs—even though it also caused small increases in central arterial stiffness. In contrast, aerobic exercise produced an increase in aterial distensibility—decreased arterial stiffness—but without an increase in blood flow.

Resistance exercise also led to a longer-lasting drop in blood pressure after exercise, compared to aerobic exercise. Collier and colleagues speculate that resistance may produce "compensatory peripheral vascular effects," which offset the increase in arterial stiffness while keeping blood pressure fairly constant.

Arterial stiffness of central vessels such as the carotid arteries and aorta has emerged as an important risk factor for cardiovascular disease. Aerobic exercise is widely recommended to reduce cardiovascular risk. Less is known about the cardiovascular health effects of resistance exercise.

The results support previous studies reporting that resistance and aerobic exercise have opposite effects on arterial stiffness, while showing that resistance exercise has unique effects on blood pressure and limb blood flow.

"The present study indicates that an acute bout of resistance exercise shows many favorable cardiovascular benefits and should therefore be considered as part of a daily exercise training program," Collier and co-authors concluded.

Especially because of its ability to increase blood flow to active muscles, weight training could be a valuable companion to an aerobic training regimen. "This may be of greatest importance to women, as they can derive important weight-bearing benefits of resistance training to help prevent and/or treat osteoporosis," Collier said.

The National Strength and Conditioning Association (NSCA) is an international nonprofit educational association that develops and presents  information regarding strength training and conditioning practices and injury prevention. NSCA bridges the gap between the scientist in the laboratory and the practitioner in the field. By working to find practical applications for new research findings in the strength and conditioning field, the NSCA fosters the development of strength training and conditioning as a discipline and as a profession.

[Source: Wolters Kluwer Health: Lippincott Williams & Wilkins]