Every single component of fitness is just as necessary as the next, for a well rounded and complete exercise program. Below you will find the major components listed, and a few reasons why each should be included in your routines.
Knowledge
This is the most important component hands down. You can't exercise properly until you have researched on your own, or have been given instructions by a trained professional, such as a personal trainer, physiotherapist or doctor. Exercising without information is like going in to the wilderness without any supplies. In the best case scenario you risk not seeing results. In the worst case, injury. There is a ton of information online so at a minimum, look up exercise techniques and read the basics before trying out a new fitness program.
Warm Up
A warm up before starting a workout is one the most important components because this is what will prepare your body for all of the other training. A warm up is like having a fitness breakfast. Like nutrition, skipping breakfast will result in a quicker burnout time half way though the day. A warm up works similarly because without one, you will burn out half way through your workout!
The warm up prevents injuries and "wakes the muscles" so your body has an idea of what to expect next. Every warm up should last 5-10 minutes and should resemble what you are about to do, on a smaller scale. For example, If you are running your warm up should be walking.
Cardiovascular Exercise
Cardiovascular exercise, known to most as "cardio" is the workout that will make your heart strong and also, aid weight loss goals the most effectively. Some people think cardio is not necessary but when you see people with big muscles, having trouble making it up a flight of stairs, it makes you think twice. Cardio is all the fun activities like running, cycling, playing tennis and swimming. It gives you muscular endurance, a strong heart and an instant feeling of wellness.
Cardio exercise should be included in to your program at least twice a week for 20-40 minutes.
Strength Training/Weight Lifting
Lifting weights is sometimes neglected because many people think that lifting weights is synonymous with big muscles. Hardly! It's actually very hard to build a lot of muscle mass for both men and women. To be quite honest those huge muscles you see on body builders are usually not natural. Instead, strength training is what gives you "tone." While you are losing weight with sustained cardio activity, it's the weights that will inflate those flattened muscles, to create a cut and defined physique. You will also build muscle but on most people, it builds tone oppose to mass, so don't worry!
Lifting weights also adds bone density and strengthens joints and ligaments which prevents osteoporosis and makes us stronger and independent for much longer. This is especially important when we reach our senior years.
Weight training should be included a minimum of twice a week. Workout times vary depending on your program but you can expect anything from 20-60 minutes.
Flexibility
Stretching is also sometimes looked over, especially after a challenging workout, when all you want to do is hit the showers! It's a very important component because flexibility training prevents injuries and keeps the body limber. If you never stretch, it won't take long for your bod to start feeling tight, achey and fatigued. Stretching is also a great tension reliever and prevents chronic pain like neck and backaches. Don't skip this one!
Stretch at the end of every workout for 5-10 minutes. It's also recommend to include a stretch workout weekly or bi weekly, such as taking a yoga class.
Balance and Agility
I group balance and agility together as a minor component because you train for balance and agility during cardio and strength training sessions, provided you're choosing exercises that target these components. In any case, I thought they deserved a special mention. Agility and balance are abilities that are fantastic for sports, but also general reaction time and injury prevention.
Compound exercises, stability ball training and outdoor (or gym floor) drills will improve your balance and agility.
Every fitness component compliments the other. If you do cardio but not weights, you will look scrawny. If you do weights but you don't stretch, you will be too tight and uncomfortable to enjoy your muscles, not to mention the good chance you will be injured all together. Include all components to get the results you want quickly, safely and effectively.
It's still possible to have a big, hearty breakfast, minus the saturated fat and cholesterol. This recipe for breakfast burritos is a healthy and delicious way to start any morning. It's high in protein, and low in saturated fat. This is a much better alternative to the greasy spoon eggs and home fries style breakfasts. 
