Can current physical activity act as a reasonable proxy measure of future physical activity? Evaluating cross-sectional and passive prospective designs with the use of social cognition models

It appears that a measure of concurrent physical activity included in a cross-sectional design can act as a reasonable proxy measure of future behavior measured in a passive prospective/longitudinal design. These findings support the use of cross-sectional designs when researchers seek a standard correlational investigation of physical activity and social cognitive constructs with the possibility that coefficients may be slightly biased upwards.