Ask for their help: One of the biggest hurdles you face is role dynamics: Your parents are used to being the caregivers and authority figures. Suddenly they feel those roles have been reversed- and your attempts to lecture, admonish or make demands will only make them feel guilty, ignorant and angry.
Play the role of a child who needs his parent’s help. Foe example: “Dad, I’m scared to see this happening. It’d help me if we could talk about it.” What Dad will hear is his son asking for advice, a familiar plea that should tug on his fatherly instincts.

Remind them how they used to feel: Make them remember what it was like to be strong and agile and in shape _ and hold out the promise of feeling that way again. Like reminding your father how much he loved playing football in high school could renew his interest in exercise.

KNOW YOUR PURPOSE: You may not convince your parent to let go of his/her old lifestyle entirely, but if s/he commits to even one healthy change, may be a daily walk, it could lead to better habits elsewhere, like improved eating habits.

Find the right time: Research shows that stress levels fall faster in the afternoon than they do in the morning, which means your parent will be calmer and more ready to listen to you if you talk to him/her after work. A long walk in the neighbourhood will get you away from interruptions and give him/her room to move. Remember: be casual, natural, intimate,nonthreatening. S/he may feel cornered by your questions. Don’t broach the topic over dinner: Eating while you re stressed causes a spike in cholesterol levels.

Present the evidence: Older people aren’t likely to change their lifestyle unless they believe that their habits are unhealthy. Use your research about your parents illness to convince them that changes in their diet and exercise routine could improve their condition. For instance, aerobic exercise is known to lower older people’s blood pressure and improve how their bodies tolerate sugar, and resistance training can increase their energy levels, make them stronger.

Listen and repeat: Nobody takes advice until he feels understood. And your parents won’t feel understood if they can’t get a word in edgewise. So shut up and listen to how they feel and what they fear. Don’t interrupt. Don’t contradict. Don’t advise. Then repeat it back to him/her, as you do with your forgetful boss.

Reward and success: Give your parent incentives to stick with the programme. Promise that the Grand kids will visit every Sunday to take a walk with them.