Methods: Students will be randomly assigned to either the intervention or the control arm. WhatsApp groups (2 per arm) will be formed within each study arm for communications. The intervention participants will receive a brief (15-minute) orientation on diet, exercise, and benefits of keeping a healthy weight; each will be instructed to wear a pedometer every day for 12-weeks with a daily step goal of 8,000. They will receive 2-3 health-promotional (walking and diet) messages per week via WhatsApp; group interaction is optional. The control group participants will receive 2-3 non-health related messages per week. Average daily steps will be assessed in all participants at baseline and 3-month follow-up using a 7-day pedometer measurement.