We recommend that appreciably the same muscular strength and endurance adaptations can be attained by performing a single set of ~8–12 repetitions to momentary muscular failure, at a repetition duration that maintains muscular tension throughout the entire range of motion, for most major muscle groups once or twice each week. All resistance types (e.g. free-weights, resistance machines, bodyweight, etc.) show potential for increases in strength, with no significant difference between them, although resistance machines appear to pose a lower risk of injury.
—Fisher, James, et al. Evidence-based resistance training recommendations. Medicina Sportiva, 15 (2011): 147-162.
Exercise is not supposed to be fun. If it is fun, then you should suspect that something is wrong.
The quote above is from an essay entitled “Exercise vs Recreation” by Ken Hutchins, posted at the Efficient Exercise website. Skyler Tanner works at Efficient Exercise and his blog is one that I follow. We have a strange connection. Skyler grew up in Fountain Hills, AZ; I live about 20 miles from there. He lives in Austin, TX, now; I lived there for eight years.
Here’s another quote from that essay:
One pound of human fat can support the energy demands of running 35-45 miles, probably more. This would require the average man to run for 6-8 hours. He would burn the calories he could easily ingest in as many minutes.
Hutchins’ essay is thought-provoking. It may change the way you think about exercise.
Steve Parker, M.D.