Improvement of Vital Capacity of healthy volunteers using Positive Reinforcement

The vital capacity (VC) is related to gender, age, weight, posture, ethnicity and anthropometric features, and it can be changed by various diseases. To achieve this measurement is necessary patient’s motivation and understanding, clarity of the information provided and ability of the researcher. The aim of this study was to analyze the impact of positive reinforcement in the measurement of vital capacity in healthy volunteers. This is a randomized clinical trial conducted with 105 healthy volunteers, randomly allocated into two groups: control (G1) and intervention (G2). The VC was measured in both groups, but for the intervention group (G2) was added to positive reinforcement. The groups were examined for the baseline VC (VC1) and, after 15 days, were reassessed (VC2). For the positive reinforcement, it was used the following phrases: "Let's go ! Come on! ... Take a deep breath !", "Pull, pull, pull !"..., "Let go slowly ...", "Loose, loose, loose, loose everything!". Both phrases of encouragement and the measurements were performed by the same evaluator. The positive reinforcement was done only during the VC measurement, during about 1 minute.