Trade-offs

There is a trade-off for everything, everything costs something.  The question is what do you want and what are you willing to give/do for it.  If you want the biggest bang for your buck, High Intensity Intervals are the way to go, group classes make it more bearable and fun, keeping track of the time to complete everything keeps it progressable and measurable, but all that has a cost too.  If you want to be truly fit across the board, you have to do endurance work too, yes, that means steady state hear rate stuff for 60-180 min, boring-ass work.  There is just no way to avoid it, depending on what you want of course.  General Broad Based Fitness Across Time and Modal Domains?  All depends on the time and modes your talking about.  Is it fractions of a second to multi-day events your idea of time domains or is 30 minutes your idea of max?  It matters.  And there is nothing wrong with 30 min being the max!  Most people don't need or want anything over 30-45 min and that's perfectly ok.  There is no need for it unless you want it for something specific.  Equally, there is nothing wrong with trying to maximize time in the gym and trading off the potential for even greater fitness, think 80/20 here.  It takes too damn long to get that extra fitness that only matters to a select few.  Same with nutrition, weighing and measuring works, but is it worth the cost, that small extra percentage of gains from it?  If you have work and a family, chances are 1 hour a night is about all you can give, if that.  In that case, make the trade, be a Bad-Ass in most things and be okay with the trade, eat paleo and forget the rest, it's not worth it.

For the others:          

“…enzymes associated with adenosine triphosphate resynthisis capacity and pyruvate-lactate interconversion are key determinants of sprinting speed.  Sprint type training has its greatest effects on the phosphagen pathways, with lesser but significant effects on glycolytic or oxidative metabolism.

            Intense, brief activities engage the phophagen pathway, especially in fast-twitch muscle fibers.  Likewise, these pathways account for much of the energy yield during the transition from rest to exercise, or from one workload to another, in all fiber types.  Although intramuscular ATP levels rarely drop more than 40-60%, several seconds of intense activity can virtually deplete creatine phosphate (CP); this is highly correlated with sprinting fatigue.

            Creatine phosphate repletion is achieved oxidatively, with a biphasic time course characterized by initial rapid (half-time 20-22 seconds) and subsequent slow (half-time ~170 seconds) components.”

-Page 478 in the 3^rd edition (emphasis added)

What does that say?  That says in order to replenish the CP (super quick energy pathway) you have to have an efficient oxydative pathway.  Ironic.  The oxidation process replenishes CP.  Does this mean O'Lifting guys would be better off doing some Oxydative work?  What about football players?  High CP work on a repetitive basis; these guys need to replenish CP, fast.  Some would argue they should do more high intensity intervals, I would argue they need both, but time is finite and there will have to be trade-offs eventually.