Changes in Peak Fat Oxidation and Aerobic Fitness During Pre-season in Sub-elite Football Players
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 50
- 试验地点
- 1
- 主要终点
- Changes in Peak Fat Oxidation During Pre-season in Sub-elite Football Players
研究概览
简要总结
Cross-sectional studies clearly demonstrate that the maximal fat oxidation (MFO, onwards referred to as peak fat oxidation, PFO) and the intensity at which it occurs (Fatmax) are higher in trained compared with untrained men and women (Maunder et al. 2018; Nordby et al. 2006; Lima-Silva et al. 2010). Furthermore, a recent study in endurance-trained males have shown a relationship between PFO and performance in an Ironman triathlon (Frandsen et al. 2017). The interest of PFO and Fatmax in endurance sports is centered on the speculation that increased fat oxidation rates during exercise would benefit endurance performance (> 4 hours) due to a glycogen sparing effect. Furthermore, it is speculated that the high amount of low-intensity training (70-80%), as seen with elite endurance athletes, might be essential in order to increase the fat oxidation capacity. However, when PFO is compared across an athletic population, football players have similar values as endurance-trained athletes (Randell et al. 2016; Randell et al. 2019; Frandsen et al. 2017), which is somewhat surprising when the different training regimes are considered.
It is noteworthy that the variations in PFO in various types of athletes and football players are considerable (Randell et al. 2016). However, different playing position in football has different work requirements, thus it might be that some of the variation seen in PFO could be related to the different playing position.
To our knowledge, no study has previously looked at the variations in fat oxidation capacity before and after a training period in athletes. Therefore, the aim of the present study is to investigate changes in peak fat oxidation and aerobic fitness during a pre-season training period in sub-elite football players. A secondary aim is to investigate if the changes are related to specific playing positions on the field. The overall hypothesis is that a pre-season training period would increase the fat oxidation capacity and aerobic fitness, and that the changes are related to specific player positions.
详细描述
Three sub-elite football teams in the Copenhagen area will be recruited for the study. The study will include two visits to our laboratory and field tests during the pre-season.
Before the participants volunteered to participate and signed a written informed consent form, the participants received both written and oral information about the content and possible risks associated with the study.
The participants arrived at the laboratory after an overnight fast (from latest 10pm). Furthermore, the participants were asked to avoid strenuous exercise 48 hours prior to the test day and eat a habitual diet, which had to be replicated before the second visit.
Testing at our laboratory includes:
- Measurements of height and weight anthropometry.
- Measurement of body composition using a Dual-energy X-ray absorptiometry (DXA) scan.
- Measurement of VO2max using a non-exercise testing method based on seismocardiography.
- Collection of a 15 ml resting venous blood sample for measurements of resting levels of hormones, metabolites and lipids in the blood plasma.
- Measurement of PFO and Fatmax during a graded submaximal running test on a motor driven treadmill.
- Measurement of VO2max on a motor driven treadmill.
- A questionnaire regarding previous and current football level, numbers of active years, playing position etc.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 否
入选标准
- •Sub-elite football player
排除标准
- •Cardiovascular and/or metabolic disease
结局指标
主要结局
Changes in Peak Fat Oxidation During Pre-season in Sub-elite Football Players
时间窗: From January until April
Peak Fat Oxidation (PFO) will be measured before and after pre-season in Sub-elite Football players, and pulmonary gas exchange will be measured during the treadmill running protocol as previously described. The fat oxidation rates will be calculated using the stoichiometric equations described by Frayn, with the assumption that urinary nitrogen excretion is negligible: Fat oxidation (g⋅min-1) = (1.67 ⋅ VȮ2) - (1.67 ⋅ V̇CO2). A 3nd-degree polynomial regression will be applied to determine PFO and the intensity at which it occurs (Fatmax) for each test individually. Changes in PFO from baseline and after 8 week pre-season will be measured and reported.
We will measure Aerobic Fitness before and after a Pre-season in Sub-elite Football Players
时间窗: From January until April
Aerobic Fitness will be measured before and pre-season in Sub-elite Football players, and pulmonary gas exchange measurements will be measured during the treadmill running protocol as previously described. VO2max will be reported both as an absolute value (ml/min) and relative to body-weight (ml/min/kg). The VO2max is determined as the highest value measured over consecutive 30 seconds. Changes in VO2max from baseline and after 8 week pre-season will be measured and reported.
次要结局
- To investigate if the possible changes in Peak Fat Oxidation are related to specific playing positions on the field(From January until April)
- To investigate if the possible changes Aerobic Fitness are related to specific playing positions on the field(From January until April)
研究者
Jørn Wulff Helge
Professor
University of Copenhagen