General Fitness

People who love to lift typically don’t look forward to cardio day. That's also the trend among runners and cyclists on the days they set aside for strength training. A study from the University of Utah looks into this separation of performance traits using lab mice.
Researchers observed how effectively some mice protected their territory by fighting off other mice. They also measured the running efficiency of mice using a treadmill.

Rodents that were successful fighters burned more oxygen while running compared to less successful fighters. Although there weren’t significant differences in body mass between runners and fighters, scientists theorized there might be small physiological differences.
General Fitness

Larger cycling events that take place over the course of several days sometimes include one or more climbing stages. What’s it take to get over the top? A study published in the International Journal of Sports Physiology and Performance analyzes the physiological demands of competing in a 9.2 KM race up a 7.1% slope.
Fourteen elite road cyclists completed the race. The first, second, sixth and final kilometers were the most physically challenging, and the race was performed at an average 90% of maximum heart rate and 90% of maximal oxygen capacity using 70% of maximum power output.

Sitting down to a high-protein meal can help support muscle mass maintenance and exercise recovery. But cracking open a sugar-sweetened beverage at that meal can have a dramatic impact on energy balance and fat storage. A study published in the journal BMC Nutrition shows what can happen.
On separate occasions, 27 healthy weight men and women in their early 20s ate a 500 calorie breakfast and lunch with 15% of the calories coming from protein and 17 grams of fat. Next time, breakfast and lunch had 30% of the calories from protein. With a reduction in carbohydrates, these meals also totaled 500 calories with 17 grams of fat.
A sugar sweetened beverage caused an average 7.2 gram decrease in fat oxidation with the 15% protein meals. The decrease in fat oxidation was 12.6% with the 30% protein meals. Researchers suspect this drop in metabolic efficiency might prime the body to store more fat.