We know that resistance training improves strength, but can it also challenge the cardiorespiratory system? In a study published in The Journal of Strength & Conditioning Research (2017; 31[3], 644—52), researchers analyzed the effects of three exercises performed three different ways, to determine the cardiorespiratory response to each.

In this study, 15 trained men performed 3 sets of 10 repetitions of biceps curls, barbell rows and knee extensions at 80% of 10–repetition maximum. The exercises were executed in bilateral, unilateral and alternating limb patterns with a 2–minute rest between sets. Heart rate and blood pressure were measured after the last repetition in each set.

As the researchers expected, increases in oxygen demand (RPP), blood pressure and heart rate were observed from pre– to postexercise in all conditions. But one exercise and format edged out the competition.

"Bilateral biceps curls caused a greater increase in RPP (first and second sets) and HR, compared with the same exercise performed unilaterally," the authors said. "Furthermore, the performance of bilateral biceps curls induced greater HR and RPP, in all sets, compared with bilateral knee extension and barbell rows."