David L. Wenos

Controlled warm-up intensity enhances hip range of motion.

&NA; Wenos, D.L., and J.G. Konin. Controlled warm‐up intensity enhances hip range of motion. J. Strength Cond. Res. 18(3):529–533. 2004.—Acute effects of active and passive warmup, proprioceptive neuromuscular facilitation (PNF), and ratings of perceived exertion (RPE) were compared during hip‐joint range of motion (ROM). Two active warm‐up treatments included (a) achieving a respiratory exchange ratio (RER) of 1.00 and (b) achieving 60% of heart rate reserve (HRR). Hydrocollator pads (HP) served as the passive warm‐up treatment. These treatments and a control were randomly assigned to increase hamstring muscle temperature of the dominant leg. Warm‐up treatments were administered to 12 men (mean 25.3 years) with a minimum of 24 hours interspersed between each treatment. A timed PNF (slow‐reversal‐hold) technique was conducted after each warm‐up treatment. Tukey tests (p < 0.05) showed ROM for RER (107.4°) was greater than all other treatments. ROM for HRR (102.8°) and HP (103.4°) did not differ from each other but were greater than the control (98.8°). Ratings of perceived exertion were lowest for RER (4.0) and highest for control (8.5). Ratings of perceived exertion for HRR (6.0) and HP (6.5) were similar. In conclusion, an active warm‐up before PNF stretching appears to be the most effective treatment to increase hip ROM. Results of RPE reinforce that active warm‐up reduces the resistance to stretch. In a field setting, it is estimated that a warmup of 70% of HRR would duplicate the muscle readiness equivalent to an RER of 1.00 before PNF stretching.

Trekking poles increase physiological responses to hiking without increased perceived exertion.

Saunders, MJ, Hipp, GR, Wenos, DL, and Deaton, ML. Trekking poles increase physiological responses to hiking without increased perceived exertion. J Strength Cond Res 22(5): 1468-1474, 2008-Trekking poles are used by hikers for improved stability and lowered leg fatigue due to increased upper body muscle involvement. However, the weight of the poles and exaggerated upper body movement when using poles may increase total energy expenditure at a given walking speed. Few studies have investigated the physiological responses of hiking with trekking poles outside the laboratory setting. The purposes of this study were to determine if trekking poles altered physiological responses to hiking on varied terrain, and whether responses between trials were dependent on the grade of the terrain. Fourteen recreational hikers completed four hiking trials over a course that included sustained sections of flat (0 ± 1% grade), steep uphill (>10% grade), gradual uphill (5% grade), gradual downhill (−5% grade) and steep downhill (<−10% grade) terrain. Subjects walked at a self-selected speed that was matched across trials using time-splits and a metronome. Two trials were conducted with hiking poles and two without poles. &OV0312;O2 was significantly elevated (p <0.05) during the pole trials (1502.9 ± 510.7 ml/min) compared to the no-pole trials (1362.4 ± 473.2 ml/min). Similarly, ventilatory efficiency (&OV0312;E) (43.1 ± 9.6; 38.3 ± 10.1 L/min) and heart rate (HR) (112.1 ± 9.7; 105.7 ± 10.4 bt/min) were significantly higher during the pole trials than the no-pole trials. However, ratings of perceived exertion (RPE) was not altered by pole condition (8.5 ± 0.7; 8.4 ± 0.8). Comparisons within each grade revealed significantly higher physiological responses for &OV0312;O2, &OV0312;E and HR in the pole-condition at all grades, with no significant variable*grade interactions. RPE measures were not significantly different between pole trials at any grade. These data suggest that trekking poles may be a beneficial tool for increasing caloric expenditure, as energy production increased during exercise without increased perceptions of effort.

Vigorous Intensity Exercise Training Improved Severity of Obstructive Sleep Apnea in a Prediabetic Individual

Obstructive sleep apnea (OSA) is a prevalent form of sleep disordered breathing that increases ones risk for numerous chronic health conditions such as cardiovascular disease and diabetes mellitus. A limited number of studies have suggested that exercise training, mostly focusing on light-to-moderate intensities, may positively impact OSA severity and other health outcomes. This case study describes a moderately active man who was diagnosed as pre-diabetic through his physician and found to likely have moderate severity OSA through at-home screening device. He underwent eight of aerobic training at vigorous intensity.