Tortosa-Martinez J, Caus-Pertegaz N, Martinez-Canales C. Group-based exercise for people with mild cognitive impairment: a pilot study. J. Hum. Sport Exerc. Vol. 8, No.Proc3, pp. S702-S710, 2013.The number of neurodegenerative diseases associated to aging, such as Alzheimers disease (AD), is rapidly increasing. Mild cognitive impairment (MCI) is diagnosed when a person presents cognitive deficits, usually memory related, but still does not meet criteria for a diagnosis of dementia. It is usually considered a transitional phase between normal aging and dementia. The benefits of exercise for people with mild cognitive impairment are not fully clear and deserve further research. The aim of this pilot study was to analyse the physical benefits of a group-based exercise program for people with mild cognitive impairment. Using a pre-post design, twenty people with MCI were recruited and divided into an experimental group (10), who followed a three-month exercise program, and a control group (10) who followed routine care. The results of this study show that engaging in a supervised exercise program was effective for improving performance in the Six Minute Walk Test (6MWT), the Timed Get Up and Go Test (TGUP), and the 8-meter walk test, implying gains in cardiovascular capacity, gait and dynamic balance. After the intervention period, the control group not only did not improve in any of the fitness tests, but also showed significant worse performance in the (6MWT) and the Tinetti total score. Thus, a supervised group-based exercise program can represent a feasible and effective strategy for improving physical function in people with MCI. Key words: MILD COGNITIVE IMPAIRMENT, PHYSICAL ACTIVITY, ALZHEIMERS DISEASE, GAIT, BALANCE.