Favourite links on Physical Activity


  1. General Introduction, Issues and References
  2. Physical Fitness Components: Outline and Basics
  3. Musculoskeletal Balance and Maintenance
  4. Cardiovascular Efficiency and Training

1. General Introduction, Issues and References

How much, and which kind of physical activity you should undertake depends on your current condition, habits, and will. Some attention must be paid to the following issues:

  • If you're not used to physical activity, taking up is mainly a psychological problem and amounts to acceptance and willingness for change.
  • Before taking up a physical activity after a prolonged period of sedentary lifestyle, visit your physician to assess your personal health hazard (e.g. heart stroke risk). You generally ought to start exercising gradually
  • Always make sure you drink enough water when you exercise, as you'll lose water through sweat (see hydration)
  • It is better to exercise regularly with sustainable levels of training, which is compatible with your family/professional constraints. Overtraining can lead to injury, to a breakdown in morale, discouragement, failure, and sometimes depression.
  • Try to find some kind of coach with prior experience with physical training.
  • At first, exercise requires a lot of will, but, gradually, you can come to enjoy it!!!

Here are a few books that I like, which integrate explanation, illustrations and exercises including considerations about health, anatomy and training:

2. Physical Fitness Components: Outline and Basics

Physical fitness include a number of different components, which are briefly outlined below, and include:

  1. Joint health, skeletal effectiveness and muscular balance;
  2. Flexibility, agility, skill; (same link as above)
  3. Muscular strength and resistance; (same link as above)
  4. Heart and vascular fitness and efficiency;
  5. Balance, sustained equilibrium (proprioception)

3. Musculoskeletal Balance and Maintenance

Body pain, such as back pain, joints pain, muscle pain, can be prevented through a number of preventive behaviours, aiming at flexibility, stability and balance in the body. Mind the following:

  • In order to avoid long term joint pain, the joint must be used regularly (through activity) and trauma should be avoided (avoid violent/careless strain on the joint).
  • Balanced diet, and especially sufficient intake of calcium, essential fatty acid, and vitamin D (see explanations about exposure to the sun). All of these elements allow the joint's constant renewal (or the joint development for children and teenagers).
  • The alignment and stability of the joint depends on the condition of ligaments, the stabilizer muscles for the joint. If the muscles on one side of the joint are too strong/too tight compared to muscles on the other side of the joint, then the joint becomes unbalanced and get a wrong alignment. (see this general introduction to musculoskeletal functions)
  • The body's flexibility is to be maintained, which means that the muscles should be extensible (as opposed to the ligaments which should remain tight for the joint's stability). When performing stretches to improve flexibility, mind the following security precautions:
    • Stretching must not be painful. A painful stretch is generally damaging the ligaments, while healthy stretching sould aim at muscle extensibility
    • Muscles flexibility, as well as muscle strength, should be balanced between agonist and antagonist muscles at each joint.

Note that, in order to avoid back pain, hip joint problems, and shoulder problems, core stability is absolutely fundamental. Besides, due to the hight degrees of freedom, the hip joints and the shoulder joints need strong stabilizer muscles groups, which should better be strengthened and balanced.

4. Cardiovascular Efficiency and Training

The main function of the cardiovascular system and of the respiratory system is to produce energy for the muscles to work. Basically, oxygen obtained through respiration is brought to the muscles cells and combined there with sugar (glucose) drawn from the blood to produce energy through a chemical reaction (called glycolysis). This reaction takes place in the muscle cells.

When you exercise, this mechanism to produce energy has to increase intensity. The heartbeat increases and you come short of breath. By training regularly over an extended period of time, you can improve the efficiency of the whole oxygen-based energy production mechanism and improve your endurance. This is called cardiovascular training or cardio-training.

If you exercise with intensity above the capacity of this oxygen-based energy production function (beyond the lactate threshold you come into anaerobic exercise), your body can (temporarily!!!) produce additional energy, and then produces lactate as a chemical by-product, often leading to cramps and muscle soreness. Cramps can be prevented or alleviated to some extent by drinking water and by stretching the muscles involved.

Cardiovascular training, alternating aerobic and anaerobic exercise, is important to prevent heart and vascular diseases as well as to good maintenance for blood sugar levels regulation, and therefore for diabetes prevention.