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Kevin A Zwetsloot,1 Casey S John,1 Marcus M Lawrence,1 Rebecca A Battista,1 R Andrew Shanely1,2 1Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC, USA; 2Human Performance Laboratory, North Carolina Research Campus, Appalachian State University, Kannapolis, NC, USA Abstract: The purpose of this study was to determine: 1) the extent to which an acute session of high-intensity interval training (HIIT) increases systemic inflammatory cytokines and chemokines, and 2) whether 2 weeks of HIIT training alters the inflammatory response. Eight recreationally active males (aged 22±2 years) performed 2 weeks of HIIT on a cycle ergometer (six HIIT sessions at 8–12 intervals; 60-second intervals, 75-second active rest) at a power output equivalent to 100% of their predetermined peak oxygen uptake (VO2max). Serum samples were collected during the first and sixth HIIT sessions at rest and immediately, 15, 30, and 45 minutes post-exercise. An acute session of HIIT induced significant increases in interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-α, and monocyte chemotactic protein-1 compared with rest. The concentrations of interferon-γ, granulocyte macrophage-colony-stimulating factor, and IL-1β were unaltered with an acute session of HIIT. Two weeks of training did not alter the inflammatory response to an acute bout of HIIT exercise. Maximal power achieved during a VO2max test significantly increased 4.6%, despite no improvements in VO2max after 2 weeks of HIIT. These data suggest that HIIT exercise induces a small inflammatory response in young, recreationally active men; however, 2 weeks of HIIT does not alter this response. Keywords: cycle ergometer, inflammatory cytokines, exercise training

(VO max). Serum samples were collected during the first and sixth HIIT sessions at rest and immediately, 15, 30, and 45 minutes post-exercise. An acute session of HIIT induced significant increases in interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor, and monocyte chemotactic protein-1 compared with rest. The concentrations of interferon, granulocyte macrophage-colony-stimulating factor, and IL-1 were unaltered with an acute session of HIIT. Two weeks of training did not alter the inflamma- tory response to an acute bout of HIIT exercise. Maximal power achieved during a VO max test significantly increased 4.6%, despite no improvements in VO max after 2 weeks of HIIT. These data suggest that HIIT exercise induces a small inflammatory response in young, recreationally active men; however, 2 weeks of HIIT does not alter this response.

The purpose of this investigation was to examine the effects of cluster set configurations on power clean technique. Ten male, recreational weightlifters performed three sets of six repetitions at 80% of one repetition max with 0 (P0), 20 (P20) or 40 seconds (P40) inter-repetition rest. During the first and second set of P0, the catch and first pull were in a more forward position during repetition 6 as compared to repetition 1, respectively. During the second set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the second pull and the loop. During the third set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the first pull, transition, and beginning of the second pull. No differences in horizontal displacement were found between repetitions 1 and 6 during P20. During each set of P0, vertical displacement decreased between repetitions 1 and 6 (1.02 + 0.07 m vs. 0.94 + 0.06 m; Mean + s). Cluster set configurations led to the maintenance of vertical displacement throughout all sets. The results demonstrate cluster set configurations with greater than 20 seconds inter-repetition rest maintain weightlifting technique to a greater extent than a traditional set configuration

The purpose of this study was to examine the effects of inter-repetition rest (IRR) on ratings of perceived exertion (RPE) in the power clean exercise in a multiple set protocol using peak power as an indication of fatigue. Ten resistance-trained males participated in four testing sessions which consisted of determination of a one repetition maximum (1RM) in the power clean exercise (session 1) and performance of three sets of six repetitions at 80% of 1RM with 0 (P0), 20 (P20), or 40 s (P40) IRR (sessions 2–4). Fatigue during all three conditions was indicated by a significant decrease in power of 9.0% (P0), 3.0% (P20) and 2.1% (P40), respectively. Significant difference in the rate of power decrease in P40 indicates less fatigue in comparison to P0 and P20. P40 resulted in a significantly lowerRPE compared to P0 and P20 (7.43 ± 0.34, 6.46 ± 0.47,and 5.30 ± 0.55, respectively). RPE increased significantly (p B 0.01) within each set (5.26 ± 0.37, 6.46 ± 0.44, and 7.46 ± 0.53; sets 1, 2, and 3, respectively). Significant difference in average RPE between the conditions indicates that RPE is not a determinant of intensity (% of 1RM) but the rate of fatigue (decreases in peak power). In addition, the fact that RPE increased between sets 1, 2 and 3 during all conditions support the same conclusion. The results demonstrate that increasing IRR in power clean training decreases the perception of effort and is inversely related to the rate of fatigue.