In the 16 week resistance training, there will be 3 sessions per week, the duration of each session will be 60 minutes, which include 10min of warm-up, 40min of main exercise, and 10min of cool-down. The intensity will be light to somewhat hard (Rating of Perceived Exertion (RPE) 11 to 13; using the Cantonese version of RPE). In resistance training, the weights (resistance) will be from participants' own bodies, dumbbells, and adjustable ankle weights.

In Tai Chi, the 16-week program will be divided into cognitive, associated, and automatic stages. The coach will apply a group teaching with individual instruction on specific movements based on participant's needs in skills learning and acquisition. The same training principles of individuality and progression as well as training log-book used in resistance training will also be applied to Tai Chi training program.

Participants in this group will not participate in any specific intervention during the whole study (the 16-week intervention and 12-week follow-up periods), but they will be asked to keep a daily log on their physical activity, medicine used, illness, diet, sleep quality and other health and physical activity related information (e.g., attending healthy eating workshops).

Participants will receive a 16-week resistance training program, with 3 times a week (a total of 48 training sessions) and 60 minutes per session intervention, which is adopted from the 12-week resistance training program introduced in the book "Growing Stronger: Strength Training for Older Adults" (Seguin et al., 2002), with minor modifications under the advice of Physical Fitness Association of Hong Kong, China (PFA).

Chinese version of RS (CRS) will be used to measure participants' resilience in the study. The CRS was modified from the Resilience Scale developed by Wagnild and Young with subsequent validation in Chinese older population and confirmed its four-factor structure: equanimity, meaningfulness, ceaseless self-improvement, and self-reliance. It is a 7-point Likert scale from 1 (highly disagree) to 7 (highly agree), with a greater score mirroring higher level of resilience. Three levels are set, with scores of 145 and above indicating moderate to high resilience, scores from 126 to 144 indicating low to moderate levels of resilience, and scores less than 126 indicating low resilience.

The functional fitness (FF) of participants will be measured using the Senior Fitness Test (SFT) battery. The SFT is a widely used measurement for functional fitness of older adults in the ageing and physical activity area. Within the SFT, the body mass index (BMI) will be used to examine the body composition of the participants.