Harvard Medical School's website provides calorie expenditure estimates for weight training. A 30-minute weight-training session burns about 90 calories if you weigh 125 pounds. If you weigh 155 pounds, the same weight-training session will result in 112 calories burned. Aerobic exercises burn calories at a notably quicker rate than weight lifting.
Note that this is a ratio, not the formulae you are looking for. So, a 15:5:15 ratio would be ideal (note the ratio of 3:1:3). The company Scotts has just released what appears to be an ideal palm fertilizer with microelements, magnesium and calcium. Consider buying a slow release fertilizer. It is more expensive but probably better for the plants and less labor intensive.
These materials typically consume nitrogen during their breakdown. Many people rake the garden of debris, apply their fertilizer, and finish with a top dressing. many growers use top dressings of organic material as a regular part of their palm tree care. Find a fertilizer that works well for you and stick with it.