Cross Country Poling Specific Motor Skill- and Strength Training.

Study Overview
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Brief Summary
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Will motor skill- and/or strength training affect technique, work economy and time performance in cross-country poling? Competitive cross-country skiers (age 16- 30) will perform a 10 weeks training intervention. They will be randomized in one of the following three groups: poling specific motor skill training 3 times per week in addition to their regular training, maximal strength training 3 times per week in addition to their regular training and a control group who only perform their regular training. Pre- and post intervention, all participants will perform tests in VO2max (running), VO2max (poling), work economy (poling), video and inertial measurement unit (IMU) analyzes of poling technique, time performance test (poling), motor skill tests and maximal strength tests.

Detailed Description
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Motor Skill- and Maximal Strength Training; Importance for Technique, Work Economy and Time Performance in Cross Country Poling Purpose The relative use of poling in classic cross-country skiing has increased over the last years. (Danielsen et al 2015). As a result of this poling performance has become increasingly important for over all classic cross-country skiing performance. Poling performance with best possible technical skills, implying high velocity with a least possible energy cost (C) should thus be beneficial. Previous research (Østerås et al 2002) has shown improved work economy in poling after maximal strength training (MST). To the investigators knowledge, the effect of motor skill training (MOT) on C has not previously been investigated. In this study MOT and MST will therefore be investigated (in two different groups of cross-country skiers), how they may affect poling technique, C, lactate threshold (LT) and poling performance. The results from this study may give further insight and knowledge in scientific based training practice. The purpose of this study is thus to investigate if: MOT results in technical changes in poling? MST results in technical changes in poling? MOT improves C in poling? MST improves C in poling? changes in 1-4 improves time performance in poling? In order to investigate this, competitive cross-country skiers (age 16- 30) will perform a 10 weeks training intervention. They will be randomized in one of the following three groups: poling specific motor skill training (10-12 x 3 repetitions maximum, RM) in specific designed cross country exercises 3 times per week in addition to their regular training. Further, maximal strength training in squat, dead lift, bench press, bench pull and pull down (2-5 x 3 repetitions RM) 3 times per week in addition to their regular training and a control group who only perform their regular training. Pre- and post intervention, all participants will perform tests in VO2max (running), VO2max (poling), work economy (poling), video and IMU analyzes of poling technique, time performance test (poling), motor skill tests and maximal strength tests.

Official Title
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Motor Skill- and Strength Training; Importance for Technique, Work Economy and Time Performance in Cross Country Poling

Conditions
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Healthy

Intervention / Treatment
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* Other: training intervention, motor skill training
* Other: training intervention, maximal strength training
* Other: control group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy, competitive cross country athletes 16-30 years old Exclusion Criteria: contraindications to maximal strength training and strength and endurance testing

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Motor skill training<br>training intervention. Poling specific indoor motor skill exercises performed 3 times pr week for 10 weeks in addition to regular training | Other: training intervention, motor skill training<br>* cross country specific motor skill strength training<br>|
| Experimental: Maximal strength training<br>training intervention. Maximal strength exercises performed 3 times pr week for 10 weeks in addition to regular training | Other: training intervention, maximal strength training<br>* general maximal strength training<br>|
| Experimental: Control group<br>Only regular training | Other: control group<br>* regular training<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time trial poling on a roller ski tarmac track | Seconds used in a 6 km track. | 10 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Video analyzes of technique | Joint angles. Unique outcome measure. | 10 weeks | 
| Analyzes of angular velocity by use of IMU (inertial movement devices) | Degree/second by use of gyrometer from the Musclelab System from Ergotest Technology. Unique outcome measure. | 10 weeks | 
| Analyzes of external force (N) in poles during poling | Force measurements by use of the Musclelab System from Ergotest Technology. Unique outcome measure. | 10 weeks | 
| Maximal pulldown strength (RM/kg) | Kilos in pulldown. Unique outcome measure. | 10 weeks | 
| Maximal leggpress strength (RM/kg) | Kilos in leggpress. Unique outcome measure. | 10 weeks | 
| Maximal pulldown power (Watt) | Watts in pulldown by use of Musclelab.System (Ergotest Technology). Unique outcome measure. | 10 weeks | 
| Maximal leggpress power (Watt) | Watts in leggpress by use of Musclelab.System (Ergotest Technology). Unique outcome measure. | 10 weeks | 
| Maximal oxygen uptake (VO2max, ml/kg/min) in running on treadmill | Ergospirometrical incremental (ramp) protocols using Cortex Metalyzer. Unique outcome measure. | 10 weeks | 
| Maximal oxygen uptake (VO2max, ml/kg/min) in poling on treadmill | Ergospirometrical incremental (ramp) protocols using Cortex Metalyzer. Unique outcome measure. | 10 weeks | 
| Lactate threshold (mmol/L blood) in poling on treadmill | Measurement of lactate using Lactate Scout (EKF Diagnostics) in different submaximal work periods up to the point reaching warm up values plus 2,3 mmol/L. Unique outcome measure. | 10 weeks | 
| Poling economy | Measurement of oxygen consumption per meter poling. Unique outcome measure. | 10 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cross country poling, motor skill, strength training