Frode Moen

Association between laboratory capacities and world-cup performance in Nordic combined

Background Nordic combined (NC) is an Olympic winter-sport performed as a ski jumping (SJ) event followed by a cross-country (XC) pursuit race employing the skating style. Purpose To elucidate the associations between sport-specific laboratory capacities and SJ, XC skiing, and overall NC performance in a world-cup NC event. Methods Twelve international world-cup NC athletes from 8 nations performed laboratory testing one day prior to participating in a world-cup NC event. Squat jumps and SJ imitations (IMIT) were performed on a three-dimensional force plate, whereas XC skiing-specific physiological characteristics were obtained from roller ski skating tests on a treadmill and an all-out double poling (DP) test. Finally, body composition was measured. Laboratory capacities were correlated against performance in SJ, 10-km XC skiing, and overall NC in the world-cup event. Multiple regression analysis was used to determine the best suited laboratory variables for predicting performance. Results Vertical IMIT velocity together with body-mass provided the best prediction for SJ performance (r2 = 0.70, p<0.01), while body-mass-normalized V˙O2peak and DP power provided the best prediction for XC performance (r2 = 0.68, p<0.05). Body-mass-normalized V˙O2peak was the only significant correlate with overall NC performance (r2 = 0.43, p<0.05) in this competition. Conclusion Overall, the concurrent development of V˙O2peak, upper-body power, and SJ-specific vertical jump capacity while minimizing body-mass within the BMI limit set by FIS should be considered in the seasonal training of NC athletes.

A Pilot Study of Impulse Radio Ultra Wideband Radar Technology as a New Tool for Sleep Assessment

STUDY OBJECTIVES To validate Impulse radio ultra wideband pulse-doppler radar technology against polysomnography (PSG) for sleep assessment. METHODS In all, 12 participants were recruited and their overnight sleep was assessed both by a Novelda XeThru radar and PSG. Two subjects had two nightly recordings, whereas 10 had one recording. Epoch by epoch (30 seconds) comparisons from bedtime to rise time were conducted. Concordance was estimated in terms of the mean difference between the radar and the PSG estimates regarding sleep onset latency, wake time after sleep onset and total sleep time. In addition, accuracy, sensitivity, specificity and Cohen kappa were calculated. RESULTS The mean difference (minutes) between the radar and the PSG registrations was -5.7 minutes (standard deviation [SD] = 22.1 minutes) for sleep onset latency, 6.4 minutes (SD = 32.5 minutes) for wake after sleep onset, and 1.5 minutes (SD = 24.6 minutes) for total sleep time. The mean values obtained for accuracy, sensitivity, specificity and Cohen kappa were 0.931, 0.961, 0.695 and 0.670, respectively. CONCLUSION Impulse radio ultra wideband radar technology is a promising tool in terms of affordable and practical objective sleep assessment. Further technical development and more validation studies are needed in order to conclude about the utility potential of this device.

Does an Experience-Based and Practice- Oriented Approach in Coaching Education Influence Coaching Efficacy Positively?

Coaching education is previously suggested to have a positive influence on coaching efficacy among coaches in sport. However, little is known about whether differences in learning approaches in formal coaching education lead to various outcomes in coaching efficacy. With this as a background, the current study explores whether coaching efficacy varies between coaches with different types of formal educational background. Special focus is put on the experience-based and practice-oriented «Topptrener» education programs. A sample of 614 Norwegian coaches from different sports such as cross-country skiing, cycling, athletics, soccer, and handball participated in the investigation. The coaches were split into three groups based on their formal educational background: (1) coaches with «conventional sport-related higher formal education», (2) coaches with «no sport-related higher formal education», and (3) coaches with «experiential and practice-oriented formal education through the ‘Topptrener’-programs». When possible, gender differences were accounted for, and years of education and coaching experience were used as covariates; the «Topptrener coaches» showed significantly higher coaching efficacy than coaches in the two other groups (p < .05). These findings are discussed with regard to applied explanations and implications, and possible future research is suggested.