Hypertension is highly prevalent among older adults, and its global incidence is increasing primarily due to the aging population. With the development of information and communication technology, smart blood pressure monitors have been developed to offer more personalized guidance to users. A smart blood pressure monitor must provide users with professional guidance, such as monitoring pregnancy-induced hypertension for pregnant women and brain health indicators for older adults. This increases user willingness and engagement. In this study, we developed a smart blood pressure monitor system called 'BP-ExerGuide' to provide a personalized exercise safety guideline for older adults in the community's smart gym. In this scenario, all smart gym devices are equipped with RFID sensors, and members can use their personal RFID cards to start a blood pressure measurement. Only when the blood pressure value meets the safety criteria for exercise, can they use the exercise devices. If an individual's blood pressure is too high, BP-ExerGuide acts like a sports coach, advising seniors to take a rest first and then start exercising once they meet the safety guidelines. The system also integrates exercise logs and blood pressure logs into a smart healthcare platform for seniors to track their physiological changes. Overall, the BP-ExerGuide system provides older adults with a safer and more personalized exercise experience while monitoring their blood pressure levels. This system improves the willingness of seniors to exercise regularly and thus promotes better health and well-being.