The Effect of Antioxidant Vitamin Supplementation on Muscle Performance and Redox Status After Eccentric Training
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 28
- 试验地点
- 2
- 主要终点
- Maximum isometric torque (torque)
研究概览
简要总结
Consumption of vitamin supplements is a common practice among athletes or people participating in health promoting exercise programs. The reason for this interest in vitamin supplements is primarily because of the observation that enhanced production of reactive oxygen and nitrogen species (RONS) influence fundamental biological processes, such as gene expression, signal transduction and enzyme activity. In a muscle and exercise physiology context, a low level of RONS is required for normal force production, whereas marked increases in RONS can cause contractile dysfunction, resulting in muscle weakness and fatigue. On the other hand RONS are involved in signaling pathways and serve to up-regulate the expression of a number of genes and can exert favorable effects such as training adaptations.
The present study will employ a valid eccentric exercise model to examine the influence of combined vitamin C and E supplementation after acute and chronic eccentric exercise on muscle damage and performance, redox status, hemolysis and lipid and lipoprotein profile.
详细描述
Historically there was a shift in the paradigm regarding the effects of antioxidant supplementation on muscle performance and redox status. In fact, back in the 80's and 90's most of the relevant studies reported "positive" effects of antioxidant supplementation on muscle performance, muscle damage and redox status. On the other hand, the last five years, an increasing number of well-received studies are appearing pointing towards the negative impact of antioxidant supplementation. Moreover, much more studies than the past are now specifically addressing the effects of antioxidant supplementation on the exercise adaptations that take place after chronic exercise. Regarding the latter, it has been reported recently that antioxidant supplementation greatly decreases training efficiency and prevents many cellular adaptations to chronic exercise. Nevertheless, the debate is still open and an equal number of recent studies have reported the reverse i.e. positive effects of antioxidant supplementation on exercise adaptations or virtually no effect of antioxidant supplementation on exercise adaptations.
Eccentric muscle work is an essential part of daily activities of humans, such as walking, and in particular, when walking downhill or descending stairs. The most notable and well-described effect of eccentric exercise is the muscle damage that peaks one to three days after exercise. Eccentric exercise can cause effects other than just muscle damage, from activation of several transcription factors to favorable changes on lipid and lipoproteins profile.
In a double-blinded fashion, men will receive either a daily oral supplementation of vitamin C (1g) and vitamin E (400IU) or placebo for eleven weeks. Following baseline tests, volunteers will have to perform an eccentric exercise session two times per week for four weeks. Before and after the chronic eccentric exercise volunteers will be subject to one session of acute eccentric exercise, and physiological measurements will be performed as well as blood samples and muscle biopsies will be collected.
The aims of the present research are to investigate:
- the effect of antioxidant vitamin supplementation for 4 weeks on muscle performance, redox status, hemolysis and lipids and lipoprotein profile,
- the effect of an acute bout of eccentric exercise on muscle performance, redox status, hemolysis and lipid and lipoproteins profile of untrained individuals supplemented with or without antioxidant vitamins,
- the effect of 4 weeks of eccentric training on muscle performance, redox status, hemolysis and lipid and lipoproteins profile of untrained individuals supplemented with or without antioxidant vitamins,
- the effect of an acute bout of eccentric exercise on muscle performance, redox status, hemolysis and lipid and lipoproteins profile of individuals trained for 4 weeks and supplemented with or without antioxidant vitamins.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 30 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Physiological body mass index (BMI)
- •Physiological health profile
- •Subject provides written informed consent
排除标准
- •Professional athlete
- •Consumed any nutritional supplement the last 3 months
- •Performed pure eccentric exercise the last 6 months
- •Non Caucasian
结局指标
主要结局
Maximum isometric torque (torque)
时间窗: Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11)
An isokinetic dynamometer (Cybex, Ronkonkoma, NY) will be used for the measurement of isometric knee extensor peak torque at 90° knee flexion. The average of the three best maximal voluntary contractions with their dominant leg will be recorded. In order to ensure that the subjects provide their maximal effort, the measurements will be repeated if the difference between the lower and the higher torque value exceeded 10%. There will be two minutes rest between isometric efforts.
Range of motion, ROM (degrees)
时间窗: Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11)
The assessment of pain-free ROM will be performed manually using the the isokinetic dynamometer. The investigator will move the calf at a very low angular velocity from 0 knee extension to the position where the subject will feel any discomfort.
Delayed onset muscle soreness, DOMS (scale 1-10)
时间窗: Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11)
Each participant will assess delayed onset muscle soreness (DOMS) during squat movement (90o knee flexion) and perceived soreness will be rated on a scale ranging from 1 (normal) to 10 (very sore).
Creatine kinase, CK (activity IU)
时间窗: Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11)
CK activity will be measured as a general indicator of muscle damage.It will be measured in a Cobas Integra Plus 400 chemistry analyzer. CK will be measured before the beginning of the supplementation (week 0), before and the week after the first bout of eccentric exercise (week 5), before and the week after the second bout of eccentric exercise (week 11).
次要结局
- Reduced glutathione, GSH (μmol/g Hb)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Oxidized glutathione, GSSG (μmol/g Hb)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Thiobarbituric acid-reactive substances, TBARS (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Protein carbonyls (nmol/mg pr.)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Catalase (μmol/min/mg Hb)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Total antioxidant capacity, TAC (mm DPPH)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Albumin (g/L)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Uric acid (μm)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Vitamin C and E (mmol/L)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Plasma hemoglobin (g/dL)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Bilirubin (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Triacylglycerols, TG (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Total cholesterol (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- High-density lipoprotein cholesterol, HDLC (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))
- Low-density lipoprotein cholesterol, LDLC (μM)(Before the beginning of the supplementation (week 0), the week after the first bout of eccentric exercise (week 5), and the week after the second bout of eccentric exercise (week 11))