Some general training principles include the following:
1) Specificity – It is important to train using proper techniques in order to produce a specific result. Every exercise that you perform should be geared towards a specific muscle group or groups to maximize your results. When you become fatigued, continue with the exercise using proper technique; however never compensate number of repetitions over form. Improper technique leads to injuries, therefore in fatigued states, less repetitions becomes more.
2) Overload – When you can perform 15 repetitions, you need to increase the weight. Increasing the weight will enhance the intensity of your workout. Overload can also be applied to increasing the frequency of the exercises, so looking at increase sets and number of repetitions.
3) Progression – As you work out your muscles you become stronger so you need to continue to increase your training stress or intensity to see results. Progression can be closely related to overload; however you are overloading your muscles by increasing the weight in small increments (2-5 pounds).
4) Variation – It is important to add variation to your program. It is more beneficial to train one body part per session than trying to do a whole body workout. You will get more bang for your buck training 1-2 muscles groups per session. As we workout, our bodies become accustom to the exercise routines that we perform, so make sure it increase the weights and switch up the exercises. For example, regular squats become boring and your muscles get use to the routine. Try overhead squats with just the bar, then with time add weight. Other squats that can be rotated into the routine include power squats, jump squats, one-legged squats, wide squats, etc.
I have referred to the work intensity multiple times in this article, so what exactly is intensity? Intensity is the most important variable related to which energy system is activated to produce energy for muscular work. For example, a sprinter uses their anaerobic energy system, where as a long distance runner (Greater than 2-5 minutes) uses their aerobic energy system. The training of energy systems involves manipulating both the intensity which ultimately leads to the duration of the activity.
The best advice that I can offer in regards to the intensity of your workout is to be make sport-specific. If you are training for a long distance run, you need to increase your muscle endurance and aerobic energy system. Some sports that utilize your aerobic energy systems include: 5 km and high runners and swimmer, soccer players, skiers, etc. If you are training for a short race like a sprint, you need to work on your power and anaerobic energy system. Some examples include: sprinters, hockey, football, volleyball, baseball players, etc. Therefore, if you are a beginner athlete work on building your endurance. Once you can do 20-30 minutes of cardio without being extremely fatigued, begin to train in a sport-specific manner. If your goal is strength training, then work on your anaerobic energy system. If you want to become a stronger, longer runner, work on your aerobic energy system.