Muscular strength and muscular endurance are not the same, although they are often mentioned together. Strength refers to maximum power and does not require oxygen, while endurance is strength over a prolonged period and does require oxygen.
Muscular strength is the ability of the muscles to lift weight. Muscular endurance is the ability to sustain exertion for a specified period of time.
Muscular endurance is an aerobic mechanism, meaning that it requires oxygen. Muscular strength is an anaerobic mechanism, meaning that it does not require oxygen as an energy source.
Improving both muscular strength and endurance will lead to increased bone mass, reduced body fat and blood pressure, and improved lipids and blood glucose level.
Improving muscular strength requires lifting heavier loads for lower repetitions. Improving muscular endurance involves lighter weights for a higher number of repetitions.
Muscular strength is determined by the maximum load that can be lifted in one repetition. Muscular endurance is measured by the maximum number of repetitions of a muscle contraction.