The effect of emotion on our ability to do things is so important. Get the emotion right get the thought right get the action right. Applying this to healthy living to get the thought right we need to rationalise to attain the correct emotion first. Visualisation is a well established technique. Image the feeling of good health and a trimmer figure. Hold the emotion. Then think of the action plan. Then act on it.
The type of exercise or diet plan is not crucial to be honest, sticking to the plan is.