Touring a fitness facility on any given day, it is easy to spot individuals who enjoy endless cardio as a preferred method of exercise. It's also easy to spot those who embrace lifting weights at high repetitions.
Generally speaking, it seems that men are always looking to build muscle mass and women are deathly afraid that they will build too much. This interpretation, however, coupled with an overemphasis on achieving a "good cardio sweat," can compromise the terrific outcomes derived from strength training.
There is no argument that cardio burns calories, however when it comes to building a body of a desirable shape (note there is a difference between "shape" and "size"), and an improvement in functional activity, then strength training should be a "must do" in every fitness enthusiasts tool box.
While lessening body fat through cardiovascular activity can undoubtedly decrease the amount of fat that comprises a person's overall body composition, this does not ensure an increase in overall lean body muscle mass, which I'll refer to as the "shape-able" part of the human body. Naturally, an indisputable effect cardio training has is its contribution to heart health.
While cardio-based activities are great for the heart, strength training will allow an individual to develop muscle throughout their entire body, which facilitates maximal power output when doing everything from shoveling a mound of dirt to getting out of one's favorite recliner.
Females do not have enough natural testosterone in their bodies to develop overly large muscles -- often the inaccurate assumption of the net effect of strength training. While performing endless repetitions of light weights will help tone a body, it is strength training that gives muscle its shape and overall muscle volume.
Men who perform strength training will frequently experience an increase in muscle volume and muscle size (hypertrophy) at any age, although decreases in testosterone throughout each decade of life beginning in the mid-twenties will limit the overall development of muscle size. Regardless of gender, strength training also increases the production of the cells responsible for strengthening the outer portion of bones (cortex) and decreasing the symptoms of osteoporosis, which results in increased porosity and brittleness in bones -- women being the most vulnerable to this disease.
While exercise literature often encourages any gravity-based movements to stave off the threat of osteoporosis, it is strength training that will have the most significant physiologic effect on developing strong bones.
Naturally, this promotes the question "how many repetitions and at what weight should a person perform while strength training?" While there are volumes of information that address the topic of strength training, the ultimate goal is to choose a weight that will result in temporary muscle "failure" between 8 and 12 repetitions. "Failure" refers to the inability to complete a full repetition. This failure range of 8-12 is fitting simply because each ensuing set of the same lift or movement will result in decreased stamina (and available energy) to complete the same number of repetitions for every set. If temporary failure is not achieved, than results will not be as significant. It is also a volume that creates the desired result while taking safety into account.
While it is significantly more demanding to lift to the point of muscle failure, it is this approach that will create both the most functional and cosmetic effects in living the healthiest life possible.
Bill Victor is the owner of Victor Fitness System Professional Fitness Trainers, Flashpoint Athletic Speed & Agility Specialists, and Performance Nutrition Consultants. He can be reached at firstname.lastname@example.org and online at http://theflashpoint.org and http://VictorFitnessSystems.com.