Paper Title
Relationship Between Marketing Mix of Whey Protein and Consumer Buying Decision in Bangkok Metropolitan

This research study aims to investigate the marketing mix factors that affect consumer buying decision of whey protein among those who regularly exercise at the fitness centers in Bangkok Metropolitan. The research samples were Bangkokians who exercised and consumed whey protein for more than six months. A set of questionnaires was used as research instrument to collect data from 217 respondents. The data were analyzed using the multiple regression technique. Research participants were obtained from probability sampling using the purposive sampling technique and stratified sampling technique. Results showed that the �promotion factor� has most positively influenced the consumers� buying decision (promotion = 0.18) at the statistically significant level of 0.01 followed by the �place factor� (place = 0.13), and then the �price factor� (price = 0.11) at the statistically significant level of 0.05, while the �product factor� did not show the statistically significant relationship with the buying decision at the 0.05 level. It was also found that the squared correlation coefficient value or R-square was 0.28 which means that factors of product, price, place, and promotion could be used to explain the variations of whey buying decision for 28 per cent. Another 78 per cent was related to other factors not investigated in this study Key words- whey protein, marketing mix, consumer buying decision