The whole muscle of which the muscle fibres are a part can develop force in several different ways, e.g. with the muscle as a whole shortening, lengthening or maintaining the same length while the muscle fibres contract. List of types of muscle contraction. Isotonic (of which there are two types: concentric and eccentric)
While some flight schools will advertise that you can get a pilot's license for around $5,000, the reality is that the cost generally works out to be more. A commercial pilot's license -- bigger plane, more than twice the flight time -- generally costs $40,000 to $50,000.
The main goal before beginning your training for the commercial license is to build your time towards the 250 total time requirement. Included in that time is 100 hours as pilot in command, and 50 hours of cross-country.