I prefer to swim below water [Skin Diving, Snorkeling, SCUBA, and such,] but I also swim above water. Not all forms of swimming are all upper body. When you swim underwater you use mostly your lower body [legs.] You get the same effect when you swim on top of the water while wearing fins. You rely more on your legs and less on your arms than you would without them.

Most of the exercises I do work the Lower Body. As a result, I've got strong muscles in my lower body (Quadriceps/Calves/Hamstrings,) but not so much in my Upper Arms (Biceps/Triceps.) Regardless of how me or anyone else is built, one thing is for sure, like others have pointed out, how the body handles Carbs vs. Fat after an intense workout is not really relevant to most Americans.

As for the 76/98% or whatever the exact numbers were efficiencty rates, that's how well the body stores EXCESS food. Preferablly, you shouldn't be eating more than your body needs. Whether you get fat with 76% or 98% Efficiency really doesn't make much difference...because you still get fat. As long as you aren't eating way too much, how efficiently you can store excess doesn't even come into play. They never seem to mention the efficiency of using the fuels. Carbs are way more efficient in this department than Fat or Protein.

His statement about High Fat vs. High Carb and satiation is misleading, because most studies use misleading definitions:

High Fat usually means 35-40% Fat, and can even be as low as just over 30%. 35% seems to be the most common as that is about how much the Average American eats nowadays.

High Carb usually means VERY High Carb/VERY Low Fat. That would be about 10-20% Fat/70-80% Carbs/10% Protein. This would be on par with an Ultra-Low Fat Diet.

High Protein is about the only one they even come close to getting right at 20-30% Protein. But, unless the "High Protein" is paired with "Low-Carb," it usually means about 40-50% Carbs, and 20-30% Fat.

A typical "High Fat" diet in most studies would be something like 35% Fat, 50% Carbs, and 15% Protein. That is still too high in Carbs. 35% is also hardly High Fat. Here's what I would define them as:

Fat:

VLow -- <20%
Low -- 20-35%
Moderate -- 35-50%
High -- 50-75%
VHigh -- >75%

Protein/Carbohydrates:

VLow -- <10%
Low -- 10-20%
Moderate -- 20-30%
High -- 30-50%
VHigh -- >50%

What happens is when they study diets using a misleading definition, such as 35% Fat being a High Fat Diet, or 40% CHO being Low-Carb is that they get incorrect results. 40% is way too high to be Low-Carb...since that would be 150-280g Net Carbs per day, with most men falling at the upper end of that range. 35% is also too low to be High Fat at 60-110g Fat per day. The low-end of that range is barely more than the current USDA Recomendations...and the high end is just barely what I would consider a minimum fat intake (>90g) for a woman at the lower end of the Caloric Scale. What they're really testing is a Moderate Fat/High Carb/Low Protein Diet and calling it a High Fat Diet. What they call a High Carb Diet is a Very Low Fat/Very High High Carb/Low to Very Low Protein Diet. When you combine large amounts of Carbs with large amounts of Fat, you have problems that you don't have when you eat plenty of Fat and Protein without an excess of Carbs.