Articles Flashcards
1
Q
Carbohydrate contribution and exercise intensity? (van Loon et al. 2001)
A
Protocol - Contribution of CHO at different exercise intensities
Results - increasing intensity increases the contribution of energy that is generated from CHO
2
Q
Relationship between muscle glycogen and exercise capacity? (Bergstrom et al. 1967)
A
Protocol
- mixed diet consumption and cycling performance
- high protein and CHO, high fat and mixed diet
- measured oxygen consumption (assess substrate utilisation), muscle biopsies, lactate and blood glucose
Results
- linear relationship between pre-muscle glycogen content and exercise capacity
- the higher the CHO intake the greater the exercise capacity
3
Q
The effect of carbohydrate intake on exercise performance and mood state? (Achten et al. 2004)
A
Protocol
- 7 trained male runners
- cross-over design
- 4 days moderate intensity & 7 days intensified training
- high CHO (8.5g/kg/d) vs low CHO (5.4g/kg/day)
Results
- speed during an 8km was maintained in the high CHO group
- 16km run time was maintained in the high CHO group
- mood state was maintained in the high CHO group
4
Q
Carbohydrate ingestion on muscle glycogen and exercise performance? (Bergstrom & Hultman 1966)
A
Protocol
- one cycling leg and one rest leg
- ingestion of CHO
Results
- cycling to exhaustion depleted muscle glycogen in the exercise leg
- CHO ingestion increased muscle glycogen stores in the exercise leg
5
Q
Effects of carbohydrate ingestion on muscle glycogen stores and performance? (Sherman et al. 1981)
A
Protocol - moderate CHO - Low CHO and high CHO - moderate CHO and high CHO Results - all groups increased muscle glycogen stores - after 7 days all had similar levels of muscle glycogen - no effect on performance
6
Q
Effect of carbohydrate loading on muscle glycogen stores over time? (Bussau et al. 2002)
A
Protocol
- 8 male
- high CHO (10g/kg BM/day) over 3days, remaining inactive
Results
- high increase in muscle glycogen stores of the first 24-72hrs
- no further increase after the next 2days
7
Q
How does altering carbohydrate availability affect the response to training? (Wojtaszewski et al. 2003)
A
Protocol
- 8 athletes
- 1hr of exercise (low MG) vs 1hr rest (high MG)
- measured muscle glycogen
Results
- altering nutrient availability can alter the response of muscle signalling molecules to a bout of exercise
- AMPK activity increases in low muscle glycogen
8
Q
Effects of train low, compete high on performance, citrate synthase and HAD activity? (Hansen et al. 2005)
A
Protocol
- knee extension
- 10wk one leg trained high MG (once a day) stores vs low (twice every other day)
Result
- no difference in max power
- significant increase in time to exhaustion with low MG
- greater increase in citrate synthase activity with low MG (oxidative metabolism)
- trend for increased HAD activity with low MG (fat metabolism)
9
Q
Effects of train low, compete high on performance? (Hulston et al. 2010)
A
Protocol
- training with high MG vs low MG
- trained at a self-selected training intensity
Results
- time trial performance increased in both groups
- high-intensity session results in a greater increase in power output for the higher MG stores
10
Q
Effects of sleep low on AMPK and p38MAPK activity? (Lane et al. 2015)
A
Protocol - sleep with low glycogen stores
Results - increases in AMPK and p38MAPK following exercise in the fasted state
11
Q
Effects of different carbohydrate nutritional interventions and exercise performance (VO2)? (Burke et al. 2017)
A
Protocol - 21 elite race walkers - 3wk isoenergetic diet - high CHO - periodised CHO - low CHO, high fat Results - low CHO, high fat had a greater increase in VO2 - greater benefit from periodised
12
Q
Effects of pre-carbohydrate feeding (fed vs fasted) on and muscle glycogen, blood glucose, plasma fatty acids and RER during exercise? (Coyle et al. 1985)
A
Protocol
- 7 subjects
- 105min cycling at 70% VO2max
- CHO meal 4hr before vs 16hr fast
Results
- muscle glycogen concentration higher in the fed condition
- blood glucose concentration dropped in the fed state prior to exercise due to insulin
- blood glucose concentration increased during exercise due to glucose uptake in the muscle
- plasma fatty acids was higher in the fasted state
- respiratory exchange ratio was higher in the fed state, indicating CHO oxidation
13
Q
Effects of varying amounts of carbohydrate intake on performance and RER? (Sherman et al. 1989)
A
Protocol
- 0 vs 312g CHO
- 45 vs 156g CHO
- 4hrs before 45min performance test
Results
- high 312 g CHO had a greater performance than 0g CHO
- there was little difference in performance between 45 and 156g CHO
- respiratory exchange ratio was highest in the high CHO meal indicating CHO oxidation
14
Q
Effects of pre-exercise feeding on performance and blood glucose concentration? (Chryssanthopoulos et al. 1989)
A
Protocol - 10 males - 2x 30km runs - 4hr before CHO meal - 4hr before placebo drink and CHO-E drink every 5km Results - no difference in performance - blood glucose concentration had an initial rise after the pre-exercise meal which returned to baseline during exercise
15
Q
Effect of having breakfast on performance? (Mears et al. 2018)
A
Protocol
- CHO, placebo, and water
- short-duration aerobic exercise
Results - increased performance in both the placebo and CHO condition
16
Q
Effect of either carbohydrate or water intake on resistance exercise and hunger? (Naharudin et al. 2020)
A
Protocol - CHO, placebo, and water
Results
- increased performance in both placebo and CHO conditions
- increased hunger in the water condition
17
Q
What is the effect of carbohydrate mouth rinse on performance? (Carter et al. 2004)
A
Protocol
- CHO (12.5%) vs placebo
- 1hr/~40km TT with or without CHO-E
Results - time trial performance was reduced with the CHO mouth rinse
18
Q
Is there a benefit to carbohydrate intake on performance? (Reviewed by Stellingwerf & Cox 2014)
A
Protocol
- CHO vs placebo
- 61 studies reviewed
Results
- 82% of the studies showed a performance benefit with CHO intake
- dose-response relationship
- CHO has a greater effect on performance as duration increases
19
Q
What carbohydrate methods can increase exogenous carbohydrate oxidation? (Jentijen et al. 2004)
A
Protocol
- glucose (1.2g/min)
- maximal glucose (1.8g/min)
- equivalent glucose (1.2g/min) and fructose (0.6g/min)
- tracer to assess CHO oxidation
Results - combined glucose and fructose can increase exogenous CHO oxidation more than glucose alone
20
Q
The effect of multiple glucose transporters on performance? (Currell & Jeukendrup 2008)
A
Protocol
- water, glucose, vs glucose and fructose
- 8 trained male cyclists
- 2hr @60% VO2max followed by a ~1hr TT
Results
- power output was higher in the glucose and fructose condition
- performance was higher in the glucose and fructose condition (19& better than water and 8% better than glucose)
21
Q
Effect of natural carbohydrate sources compared to gels on performance? (Salvado et al. 2019)
A
Protocol - potatoes vs CHO gels
Results
- natural CHO requires a larger intake fo foot to achieve the same volume of CHO compared to the hell
- there was no difference in improvements in time trial performance
- greater GI symptoms with natural CHO
22
Q
Effect of different carbohydrate drink patterns (volume and frequency) on exogenous carbohydrate oxidation? (Mears et al. 2020)
A
Purpose
- to determine how the pattern of CHO ingestion during running effect exogenous and total CHO oxidation rates and the reported measures of GI comfort
Protocol
- water, 50mL CHO every 5min vs 200mL CHO every 20min
- 12 males (26+/-7yrs, 67.9+/-6.7kg, 68+/-7ml/kg/min)
- 100min run @ 70% VO2max
Results
- a higher volume, low-frequency drink increased exogenous CHO oxidation, this may be due to increased gastric pressure and subsequent emptying rate
23
Q
The effect of hydrogel technology on performance? (Mears et al. 2020)
A
Protocol - hydrogel vs drink intake in cyclists -2hr preload followed by a 20min TT Results - no difference in performance between the hydrogel and an equivalent drink
24
Q
The effect of carbohydrate enriched diet on the recovery of muscle glycogen after exercise? (Peihl 1974)
A
Protocol
- 4 subjects
- CHO enriched diet (60g)
- 1hr endurance exercise followed by 1hr repeated efforts on the bike
Results
- very rapid initial glycogen resynthesis after exercise following CHO ingestion
- glycogen synthase activity driving glycogen synthesis is heavily influenced by muscle contraction resulting from the exercise
- insulin-independent phase from 10-15min
- levelling off after 15min
25
The effect of exercise on muscle glycogen resynthesis? (Bergstrom & Hultman 1966)
Protocol - exercise leg vs rest leg
| Results - glycogen resynthesis is driven by muscle contraction from exercise
26
The effect of the timing of carbohydrate intake on glycogen synthesis and glycogen stores? (Ivy et al. 1988)
Protocol - immediate feed vs 2hr delay (depleted glycogen)
Results
- immediate feeding increased muscle glycogen storage within the first 2hrs
- the 2hr delay feeding had similar glycogen stores as the immediate feeding group after 4hrs
- total rate of muscle glycogen storage of the 4hr was increased in the immediate feeding group
- The insulin-independent phase of rapid muscle glycogen synthesis seems to be driven by low muscle glycogen and contraction-induced factors resulting in an increase in glucose transport
27
The effect of the timing of carbohydrate intake on glycogen stores in team sport athletes? (Bradley et al. 2017)
Protocol
- immediate feed vs 2hr delay
- 6g/kg CHO
- rugby players
Results
- post-exercise muscle glycogen stores were similar between the two groups
- 48hr post-exercise the immediate feed had a greater increase in muscle glycogen compared to the 2hr delayed feed
28
The effect of carbohydrate and protein ingestion on muscle glycogen resynthesis? (Van Loon et al. 2000)
Protocol
- low CHO (0.8g/kg/hr)
- high CHO (1.2)
- CHO (0.8) and protein (0.4)
Results
- CHO and protein had a bigger insulin response
- the addition of protein when CHO is insufficient can help with a full CHO resynthesis programme, due to leucine in protein
29
What are the effects of hypohydration on endurance and cognitive performance in temperate-warm-hot conditions? (Sawka et al. 2007?
Protocol - dehydration
Results - dehydration of 2% body mass degrades aerobic exercise and cognitive/mental performance in temperate-warm-hot environments
30
The effect of hypohydration on physiology? (Montain & Coyle 1992)
Protocol - 4% dehydration in a 2hr period
Results
- hypohydration decreased SV and Q
- hypohydration increases HR
- hypohydration increases core body temperature
31
The effect of hypohydration on the perception of effort and thrist? (Casa et al. 2010)
Protocol - outdoor run in the heat
| Results - hypohydration increases perceived exertion, thermal sensation and thirst
32
The effect of hypohydration on running velocity? (Armstrong et al. 1985)
Protocol - a diuretic drug used to increase urine output and hypohydration
Results - running velocity is greater
33
The effect of hypohydration and temperature on endurance performance? (Keneflick et al. 2010)
Protocol
- 3hr of heat exposure at 50C
- dehydration vs euhydration
Results
- in all temperatures, the dehydration performance was impaired
- dehydration has a greater effect on performance as the temperature increases due to increased skin temperature
34
The effect of hypohydration on endurance performance? (Streams et al. 2009)
Protocol
- 24hr fluid restriction followed by exercise
- dehydration vs euhydration
Results - performance was decreased when dehydrated
35
The effect of hypohydration on exercise, contrasting views - weight loss? (Zouhal et al. 2011)
Protocol - marathon
Results
- an increase in weight loss results in increased performance (substantial variability)
36
The effect of hypohydration on exercise, contrasting views - sweat rate? (Dion et al. 2013)
Protocol - run
Results
- The faster you run the greater the sweat rate
- No relationship between running speed and drink frequency
37
The effect of hypohydration on exercise, contrasting views - weight loss? (Zouhal et al. 2013)
Protocol - marathon running
| Results - Some elite marathon runners lost ~10% of body weight
38
The effect of hypohydration on plasma volume, thirst, RPE and endurance performance? (James et al. 2017)
Protocol
- blinding
- 8x 5min exercise (5min rest) followed by a 15min TT
- dehydration vs euhydration
Results
- dehydration results in a substantial loss in plasma volume compared to euhydration
- dehydration had a substantial increase in thirst compared to euhydration
- dehydration caused a greater increased RPE compared to euhydration
- dehydration decreased performance relative to euhydration
39
The effect of blinding and hypohydration on plasma volume, thirst, RPE and endurance? (Funnell et al. 2019)
Protocol
- blinded vs unblinded
- dehydration vs euhydration
- cycle 150min followed by TT
Results
- dehydration resulted in a substantial loss in plasma volume, an increase in thirst and an increase in RPE relative to euhydration
- there was no difference in response between the blinded and unblinded group
- dehydration resulted in similar performance deficits in the blinded and unblinded groups
40
The effect of thirst on performance? (Adams 2018)
Protocol
- 2hr preload provided with a small amount of fluid every 5min
- dehydration (DEY-NOT-THIRST) vs euhydration (EUH-NOT-THIRST)
Results - even in the absence of thirst dehydration impairs performance
41
The effect of induce-dehydration and habitual dehydration on endurance? (Fleming & James 2014)
```
Protocol
- dehydration and euhydration
- familiarisation
- VO2peak
Results
- dehydration impaired performance by 6%
- dehydration habituation impaired performance by 1%
```
42
The effect of the rate of drinking on drink retention? (Jones et al. 2010)
Protocol - drink over 1hr vs 4hrs
| Results - for a given drink volume, drinking slower increases drink retention
43
The effect of CHO rehydration on fluid retention, plasma volume and serum osmolality? (Clayton et al. 2014)
Protocol
- rehydration following exercise
- 1% body weight loss
- 2% vs 10% CHO
Results
- more urine produced in the 2% CHO relative to the 10% CHO drink
- no recovery of plasma volume following rehydration - due to hypertonic CHO content
- serum osmolality continues to increase after 2L
44
Does hydration really matter in terms of recovery? (Funnell et al.)
Protocol
- voluntary recovery
- exercise bout to loss 2% BW
Results
- resting showed no change in body mass and urine serum osmolality
- exercise had a decrease in body mass and an increase in urine serum osmolality
- indicts possibly some carryover effects of hypohydration to the next day/session
45
The effect of a high ketosis diet with a caloric restriction on exercise performance and substrate utilisation? Limitations? (Phinney et al)
Protocol
- 10wk balanced diet vs 4wks ketogenic diet (85% fat, <20g/day CHO)
- 62-64% VO2 max to exhaustion in a fasted state
Results
- time to exhaustion was similar between diets
- substrate utilisation was preferential to fat oxidation in the ketogenic diet
- there was no detriment of a ketogenic diet on performance
Limitation
- not randomised assignment to each diet (balanced followed by ketogenic)
- balanced diet was prescribed, therefore is an intervention
- exercise task favours low CHO adaptation
46
The effect of a high-fat diet on substrate metabolism and exercise performance at different intensities? (Lambert et al. 1994)
Protocol -
70%fat vs 70% CHO diet for 2wks
- Wingate test followed by an 85% Wpeak to exhaustion and followed by a 50% Wpeak to exhaustion
Results
- Fat diet reduced reliance on CHO and increased fat oxidation by changing RER
- CHO stores pre-exercise were lower in the fat diet
- Wingate performance was similar
- 85% Wpeak performance was greater in the CHO diet
- 50% Wpeak performance was greater in the fat diet
- differential performance benefit depending on the intensity of exercise
47
The effect of a high-fat diet on substrate utilisation over 15days? (Goedecke et al. 199)
Protocol
- 69% fat diet form 15days
- 2.5hrs at 63% Wpeak
Results - shift in substrate utilisation from CHO to fat as early as 5days
48
The effect of a high-fat diet followed by CHO pre-loading on substrate utilisation and fat oxidation? (Burke et al. 2002)
Protocol
- high fat (4.4g/kg/day) for 5 days followed by high CHO (9.3g/kg/day) for 1 day and a high CHO pre-exercise meal
- 2hr at 70% VO2max
Results
- fat is preferentially oxidised, even after the fat adapt condition
- high CHO pre-loading replenished muscle glycogen stores
- we can shift metabolism by ingesting a higher fat diet, and CHO can still be spared when muscle glycogen stores are restored
49
The effect of a high-fat diet on different types of exercise performance? (Unknown)
Protocol
- high fat (68%) vs high CHO (68%) for 6days followed by CHO loading (8-10g/kg) on day 7
- 100km TT interspersed with 1 and 4km sprints
- no pre-exercise meal, but CHO ingested during exercise
Results
- 100km performance was similar
- 4km sprint performance/power was lower in the high-fat diet
- RPE was the 4km sprint was higher in the high-fat diet
50
The effect of a high-fat diet on exercise performance? (Burke et al.)
```
Protocol
- high CHO (8.6g/kg/day)
- periodised (8.6 throughout the day)
- high fat (75-80% fat, <50g/day CHO)
- 3wk exercise training and diet
- 10km race walk
Results
- performance was better in race 2 - training effect
- high-fat diet had no performance benefit
```
51
The effect of a high-fat diet on pyruvate dehydrogenase kinase (PDK)? (Peters et al. 2001)
Protocol - low CHO, high fat diet
Results
- PDK (isoform found in muscle) activity increases after 3 days of a low CHO, high fat diet
- PDK inhibits pyruvate dehydrogenase which slows down CHO metabolism
52
The effect of a high-fat diet on pyruvate dehydrogenase (PDH) and substrate utilisation? (Stellingwerff et al. 2006)
Protocol
- high-fat vs CHO
- 20min steady state followed by 1min sprint at 150% peak power output
Results
- pyruvate dehydrogenase activity was impaired in the fat diet
- metabolic shift that is preventing effective CHO utilisation
53
The effect of a high-fat diet on compounds of fat oxidation in rats? (Yun et al. 2020)
Protocol - high fat vs low fat for 12wks
Results
- CD36, FABP, CPT1 and Fat-P1 expression increased following a high-fat diet
- all involved in fat metabolism
54
The effect of the 'Exercise Pill' on markers of carbohydrate and fat oxidation? (Feng et al. 2013)
Protocol - cell-cultures using GW501516 'exercise pill'
Results
- when treated some markers of fat and CHO oxidation increase
- PDK4 -> PDH -> slows CHO metabolism
- CPT1 -> FA enters mitochondria -> increase fat oxidation
- CD36 -> FA enters muscle cell -> increase fat oxidation
55
The effect of a high-fat diet on the healthspan in mice? (Roberts et al. 2017)
Protocol
- high CHO (65% CHO)
- low CHO high fat (70% fat)
- ketogenic diet (89% fat)
Results
- changes in fat content indicative of a ketogenic diet seem to improve survival
- no differences were seen in young and middle-aged mice but improvements are seen with the ketogenic diet in older mice
56
What is the extend of dietary supplement use? (Depiesse)
```
Protocol - survey at international championships between 2005-2007
Results - supplements were used by 85% of respondents
Reasons for supplementing
- 71% - aid in recovery from training
- 65% - convenience
- 52% - to improve health
- 48% - to improve performance
- 40% - to prevent or treat an illness
- 29% - to compensate for a poor diet
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57
The effect of norandrostenedione supplement contamination on drug tests? (Watson et al. 2010)
Protocol
- after a baseline urine sample subjects ingested a supplement prepared to contain a known quantity of 19-norandrostenedione
- all urine passed over the next 24hr period was collected, the volume measured and an aliquot taken
- all samples were analysed for the metabolites 19-norandrosterone (19-NA) and 19-noretiocholanolone (!(-NE) using gas chromatography-mass spectrometry
Results
- timing matters - likely positive drug test after supplement ingestion, but may not occur later in the day
- dosage matters - however, even small dosages produced positive test
- mode of contamination - greater accumulation in circulation combined with water than compared to an energy bar
58
The effect of caffeine on endurance performance? (Graham & Spriet 1998)
Protocol - 0, 3. 6 and 9mg/kg
| Results - caffeine enhances endurance performance (inverted U hypothesis)
59
The effect of caffeine between users and non-users on performance? (Bell & McLellan 2002)
Protocol
- users vs non-users
- caffeine vs placebo
- 80% VO2max to exhaustion
Results
- caffeine increased performance in both groups
- caffeine was only effectively better than placebo when consumption was within 1-3hrs of exercise
- non-users improved more in the caffeine trial compared to users
60
The effect of habitual caffeine ingestion on performance? (Beaumount et al. 2016)
Protocol
- placebo vs caffeine
- 28 day intervention
- 60min cycle trial followed by a 30% capacity test
Results
- increase in performance following caffeine ingestion
- decrease in performance when habituated to caffeine
61
The effect of insulin infusion on carnitine? (Stephens et al. 2006)
Protocol - insulin infusion
| Results - insulin infusion can increase total muscle carnitine
62
The effect of chronic carnitine supplementation on performance? (Wall et al. 2011)
Protocol - CHO (80g) or carnitine (2g) and CHO twice a day for 24wks
Results
- 0.1% increase in muscle carnitine/day
- improvements in performance with carnitine ingestion
63
The effect of the placebo effect in blinded and unblinding effects on exercise performance? (Clark et al. 2000)
Protocol
- blinding vs unblinding
- water vs placebo
- 1hr TT (40km)
Results
- small ergogenic treatment in unblind trials - small worthwhile increase in endurance power
- blinding subjects increases individuals differences to endurance effort which resulted in reduced precision of performance outcomes in control trials
- when blinded you lose the athlete feedback
64
The effect of the placebo effect in electrolyte supplementation effects on exercise performance? (Hulston & Jenkendrup 2009)
Protocol
- water placebo vs electrolyte
- 2hr cycle followed by TT
Results - 11% difference between time trial performance
65
The effect of ketone ingestion with carbohydrates on muscle glycogen post-exercise? (Cox et al. 2016)
Protocol
- CHO vs CHO + ketone
- fasted endurance exercise (2hr at 70% VO2max)
Results - muscle glycogen post-exercise was maintained following CHO ingestion with a ketone ester
66
The effect of ketone ingestion with carbohydrates on lactate and exercise performance? (Cox et al. 2016)
Protocol
- CHO vs CHO + ester
- fasted exercise (1hr at 75% Wmax + 30min TT)
Results
- lower lactate production following CHO ingestion with a ketone ester
- increase TT performance following CHO ingestion with a ketone ester
67
The effect of ketone ingestion with carbohydrates on B-hydroxybutyrate and exercise performance? (Evans & Egan)
Protocol
- CHO vs CHO + ester
- Fed exercise (1hr preload following 10km TT)
Results
- increase in plasma B-hydroxybutyrate following CHO ingestion with a ketone ester
- no difference in performance
68
The effect of ketone ingestion on B-hydroxybutyrate, muscle glycogen, muscle triglycerides, substrate utilisation and exercise performance? (Poffe et a. 2020)
Protocol
- control vs ketone ester
- fed state
- 3hr of stimulated stage race (IMT, TT and sprint)
Results
- increase in plasma B-hydroxybutyrate following ketone ingestion
- no difference in TT or sprint performance
- no difference in muscle glycogen levels
- no difference in muscle triglycerides
- no difference in substrate utilisation
69
The effect of endurance and resistance training on mitochondrial and myofibrillar protein synthesis between trained and untrained people? (Wilkinson et al. 2008)
Protocol
- endurance vs resistance training 10wks progressive
- trained vs untrained
- stable isotope used to determine myofibrillar and mitochondria protein synthesis
Results
- in untrained individuals, endurance training increased mitochondrial protein synthesis
- in untrained individuals, resistance training increased mitochondrial and myofibrillar protein synthesis
- in trained individuals, endurance training increased mitochondrial protein synthesis
- in trained individuals, resistance training increases myofibrillar protein synthesis
70
The effect of resistance exercise on net protein balance? (Phillips et al. 1997)
Protocol
- resistance exercise
- muscle protein synthesis and breakdown measured at 3, 24 and 48hrs
Results
- at rest, there is a negative protein balance
- resistance exercise increases MPS 3hrs post-exercise that decreases to baseline over time 48hrs post-exercise
- resistance exercise increases muscle protein breakdown 3hrs post-exercise that decreases to baseline overtime 24hrs post-exercise
- resistance exercise increases muscle protein balance but is still negative without protein intake
71
The effect of the timing of protein intake on muscle protein synthesis? (Rasmussen et al. 2001)
Protocol - 1hr vs 3hrs of an amino acid-CHO mixture
Results
- no difference in MPS between groups post-exercise
- no anabolic window
72
The effect of the distribution of protein intake on muscle protein synthesis? (Artea et al. 2013)
```
Protocol
- 10g every 1.5hrs
- 20g every 3hrs
- 40g every 6hrs
Results - 20g every 3hrs maximised MPS
```
73
The effect of the amount of protein intake on muscle protein synthesis? (Witard et al. 2014)
Protocol
- 0, 10, 20 or 40g of whey protein
- unilateral low-body exercise
Results - 20g of whey protein maximised MPS post-exercise and at rest
74
The effect of the amount of protein intake on muscle protein synthesis? (Moore et al. 2009)
Protocol
- 0, 10, 20 or 40g of egg protein
Results - 20g of egg protein maximised MPS post-exercise and at rest
75
The effect of the protein amount on muscle protein synthesis? (MacNaughton et al. 2016)
```
Protocol
- 20g vs 40g of whey protein
- low vs high lean body mass
- whole-body resistance exercise
- males
Results
- no effect of lean body mass
- 40g whey protein increased MPS greater then 20g
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76
The effect of gender on muscle protein synthesis? (West et al. 2012)
```
Protocol
- male vs women
- 25g whey protein
- lower body resistance exercise
Results - no differences in MPS between genders
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77
Protein source and muscle protein synthesis? (Wilkinson et al. 2007)
Protocol - milk vs soy
| Results - milk protein increase MPS more than soy
78
The effect of the source of protein on muscle protein synthesis? (Tang et al. 2009)
```
Protocol
- 10g of whey, casein or soy
- provided 10g EEA (~22g protein)
Results
- whey > soy > casein effects on MPS when consumed post-exercise
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79
The effect of the source of protein on muscle protein synthesis? (Monteyne et al. 2020)
Protocol - mycoprotein (Quorn) vs milk protein
| Results - mycoprotein increases MPS more than milk protein
80
The effect of the rate of protein intake (bolus vs pulse) on muscle protein synthesis (West et al. 2011)
Protocol - bolus vs pulse feed
| Results - rapid delivery of amino acids increase MPS
81
The effect of co-ingestion of carbohydrate and protein on muscle protein synthesis? (Staples et al. 2011)
Protocol - 25g whey vs 25g whey + 50g CHO
| Results - no effect of CHO on MPS
82
The effect of protein intake on overnight recovery of muscle protein synthesis? (Res et al. 2012)
Protocol
- evening exercise followed by post-exercise and pre-bed drink
- 0 vs 40g casein protein
Results - pre-bed protein increased overnight MPS
83
The effect of consuming whole eggs or egg whites on muscle protein synthesis? (Tang et al. 2009; Van Vilet et al. 2017)
Protocol - whole eggs vs egg whites
| Results - despite the same amount of protein intake whole eggs were better at increase MPS than egg whites
84
The chronic effects of post-exercise milk intake on body composition? (Hartman et al. 2007)
Protocol - 12wk resistance training with the intake of milk, soy or CHO
Results - milk enhanced body composition chances with resistance exercise with greater increases in body mass, fat and bone-free mass and fat mass
85
The chronic effects of post-exercise milk intake in females on body composition? (Joss et al. 2010)
```
Protocol
- 12wks resistance training
- milk or CHO
- females
Results
- milk ingestion increases lean mass
- milk ingestion resulted in a substantial decrease in fat mass
- milk enhanced body composition changes with resistance exercise
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86
The effect of combining protein intake with carbohydrates on muscle protein synthesis? (Hultson et al. 2011)
Protocol
- 8 males
- 3hr cycling a 3hr recovery
- 0.49g/kg/h CHO vs CHO + 0.16g/kg/h protein
Results - protein intake increase mixed MPS during recovery`
87
The effect of combining protein intake with carbohydrates on myofibrillar and mitochondrial muscle protein synthesis? (Breen et al. 2011)
```
Protocol
- 10 trained cyclists
- 90min cycling and 4hr recovery
- 50g CHO vs CHO + 20g protein
Results
- protein intake increases myofibrillar MPS
- no change in mitochondrial MPS
```
88
The effect of combining protein intake with carbohydrates during exercise on exercise performance? (Breen et al. 2010)
Protocol
- 12 trained cyclists
- 2hr steady state followed by 1hr performance tests
- 65g/h CHO vs CHO + 19g/h protein
Results
- cycling performance was similar between trials
- no ergogenic effect of consuming protein during exercise
89
The effect of combining protein intake with carbohydrates on post-exercise rehydration? (James et al. 2011)
Protocol - exercise-induced dehydration followed by rehydration with 65g/l CHO or 40g/l CHO + 25g/l milk protein drink
Results - the addition of milk protein-enhanced rehydration
90
The effect of additional protein intake to carbohydrates on exercise training adaptations? (Ferguson-Stegall et al. 2011)
Protocol
- 16 men and 16 women
- 5 sessions/wk for 4.5wks
- CHO + protein, CHO vs placebo
- drink intake immediately and 1hr post-exercise
Results
- greater increase in VO2 max following CHO protein intake when compared to CHO and placebo
- CHO protein intake enhanced adaptation to endurance training
91
The effect of alcohol on muscle protein synthesis? (Parr et al. 2014)
Protocol
- 25g protein vs 25 CHO shake post-exercise after alcohol consumption
- alcohol vs placebo
Results - alcohol ingestion in larger amounts reduces MPS
92
The effect of physical activity on genetic predisposition? (Wang et al. 2017)
Protocol
- 9390 women and 5291 men
- followed for 20yrs
- estimated 4yrs change in BMI and physical activity
Results - high levels of PA protect against a genetic predisposition
93
The effect of exercise on leptin levels? (King 2015)
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Protocol
- exercise vs control
- 1hr running
- followed fro 7hr on day 2
Results - leptin levels were 1/3 lower the day after exercise compared to controls
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94
Interaction between homeostatic signals (leptin) and hedonic processes? (Rosenbaum et al. 2008)
Protocol - individuals with severe obesity asked to lose 10-15% body mass
Results
- leptin reversible changes in the activation of brain centres is linked to the emotional control of eating
- leptin is a key player in response to energy balance which is responsible for triggering reward-related areas in the brain to want to eat more
- interconnected system between our hedonic and homeostatic systems that help to regulate energy balance
95
What is the interaction between GLP-1 therapy and appetite? (Blunder et al. 2017)
Protocol - GLP-1 therapy vs control
| Results - GLP-1 therapy decreases the frequency, strength and control of food cravings; decreased pleasantness of meals
96
What is the effect of ghrelin infusion in fed vs fasted state? (Goldstone et al. 2014)
Protocol - ghrelin infusion in a fed vs fasted
Results - In the fed-state, ghrelin infusion increases the appeal of high-energy food and activation of hedonic appetite centres compared to fasted
97
The effect of different types of exercise on energy expenditure? (Kelly et al. 2013)
Protocol - continuous, HIIT 1, vs HIIT 2
Results
- energy expenditure was greater during HIIT
- post-exercise energy expenditure (rapid phase) was slightly higher 1hr post-exercise
- post-exercise energy expenditure (slow component) there was no difference between groups
98
The effect of weight loss on resting metabolism? (Forthergill et al. 2016)
Protocol - people with severe obesity were asked to complete a TV programme to lose the most amount of weight
Results - after 30wks weight loss the predicted the metabolic rate was higher than actual metabolic rate - linked to metabolic adaptation
99
The effect of weight loss on exergy expenditure during physical activity? (Foster et al. 1995)
Protocol - 3.2, 4, vs 4.8km/h walking speed
Results
- energy expenditure elicited through moving at these different speeds decreases
- muscle is more efficient
- decrease body mass
- decreased energy cost of movement
100
The effect of weight loss on appetite hormones? (Sumithran 2011)
Protocol - lose 12-13% body mass
Results
- after weight loss ghrelin levels were higher and even higher after a year of weight maintenance
- after weight loss amylin, CCK and PYY levels were lower and even lower after a year of weight loss maintenance
101
The effect of short term hyperenergetic, high-fat feeding on appetite? (Thackray et al.)
Protocol - overfeeding over 7 days
Results
- overfeeding elicits subtle changes in appetite, appetite-related hormones and food reward
- no change in resting metabolic rate
102
What is the individual variation on overfeeding responses? (Bouchard et al. 1994)
Protocol - overfeed 100kcal/day for 100days
Results
- 34% excess energy dissipated for the cohort
- stronger within-pair response - genetic basis to the response to weight gain
- similar finding with weight loss response to exercise
103
How does exercise in the heat affect performance? (Galloway & Maughan 1997)
Protocol
- 4, 11, 21 and 31C
- cycling time to exhaustion @ 70% VO2max
Results
- time to exhaustion was severely impaired at 31C
- optimal temperature for performance seemed to be 11C
104
The effect of hydration on performance and core temperature? (Pitts et al. 1944)
Protocol - control, water ad-libitum. water equal to sweat
Results
- greater hydration increases performance time
- greater hydration saw a greater increase in temperature due to higher work
105
The effect of fluid intake on core temperature? (Montain & Coyle 1992)
Protocol
- 8 trained cyclists
- 2hr @ 62-67% VO2max
- 0, 20, 48 and 81% fluid replacement
Results
- the larger the fluid intake the bigger the attenuation in core temperature
- larger fluid retention attenuated hyperthermia
- able to maintain SV -> maintain Q -> maintain skin blood flow -> maintain heat dissipation
106
The effect of ice slurry ingestion on performance and core temperature? (Siegel et al. 2010)
Protocol
- 10 males ran to exhaustion in 34C
- 7.5g/kgBM of cold water (4C) vs ice slurry (-1C)
Results
- ice slurry improved performance
- ice slurry reduced core temperature with increases the potential rise in temperature
107
The effect of ice slurry ingestion on sweat loss and skin temperature? (Morris et al. 2016)
Protocol
- 9 males
- 85min cycle at 55% VO"max in 33.5C
- 3.2ml/kgBM at 15, 30 and 45min of thermo-neutral water (37C) vs ice slurry (1.5C)
Results
- ice slurry reduced whole-body sweat loss (abdomen control)
- no change in skin temperature
108
The effect of electrolyte supplementation on performance and plasma volume? (James et al. 2015)
Protocol
- 9 males
- 48hr dietary control
- time to exhaustion @ 60% VO2max in 35C
- control, energy restriction with electrolyte supplementation, vs energy restriction with placebo
Results
- control group and electrolyte supplementation maintained plasma volume
- placebo group had a reduction in plasma volume
- performance was maintained following electrolyte supplementation
109
The effect of temperature and exercise on muscle glycogen and blood lactate? (Fink et al. 1975)
Protocol - 3 bouts of 15min at 30C or 9C
Results
- in the cold at rest, there is an increase in muscle glycogen loss compared to the heat
- in the heat during exercise the was an increase in muscle glycogen loss and blood lactate compared to the cold (linked to a reduction in blood flow meaning less oxygen reaches the muscle for oxidative metabolism)
110
The effect of exercising at different temperatures on glycogenolysis, RER, VO", muscle glycogen and adrenaline/noreadrenaline? (Febbraio et al. 1996)
Protocol
- 7 endurance trained
- 40min cycle at 65% VO2max
- 20C vs 3C
Results
- increases in glycogenolysis in the heat
- RER is lower in the warmer condition
- VO2 is similar
- muscle glycogen utilisation was greater in the heat
- increased adrenaline and noradrenaline in the heat which influences muscle glycogen content
111
The effect of exercising at different temperatures and acclimation on gastric emptying, core temperature and performance? (Neufer et al. 1989)
Protocol
- neutral environment un-acclimated
- Hot environment un-acclimated
- Warm environment un-acclimated
- Warm environment, acclimated, euhydrated
- Warm environment, acclimated, 5% hyperhydrated
Results
- litter differences between warm and neutral temperatures
- hot environment was detrimental to core temperature and performance
- core temperature was less with hydration
- gastric temperature was better with acclimation
- gastric emptying was better with hydration
- the warmer they got the worse they got at gastric emptying
112
The effect of hydration on gastric emptying? (Rehrer et al. 1990)
Protocol - 4% dehydration then given a drink
Results
- dehydration cause more fluid to remain in the stomach
- reductions in blood flow in the GI system -> unable to move fluid out of the stomach and less being taken up by the intestine
113
The effect of acclimation hydration status on aldosterone and heart rate? (Garrett et al. 2014)
Protocol
- acclimation period euhydrated or dehydrated
- 5wk washout
- heat stress test
Results
- dehydration increased aldosterone secretion
- dehydration resulted in a slight tendency to decrease heart rate
114
The effect of protein intake on plasma volume and albumin? (Goto et al. 2010)
Protocol
- acclimation with protein vs control
- 5day 30min @ 70% VO2max
Results - plasma volume, total protein and albumin increased with protein intake compared to placebo
115
The effect of paracetamol on core temperature and performance when exercising in the heat? (Burtscher et al. 2013)
Protocol
- 7 students
- 2hr at 70% VO2max in 30C - 500g acetaminophen vs placebo
Results
- core temperature slightly lower with ACT
- no effect on running performance
116
What are the physiological responses to the cold at rest? (Vallerand & Jacobs 1989)
Protocol
- 10C vs 29C
- physiological response to being in the cold at rest for 2hrs
Results
- free fatty acid mobilisation reduced - vasoconstriction reduced blood flow to the subcutaneous tissue
- muscle glycogen utilisation increases - hypoglycemia stops shivering
- greater CHO oxidation
117
The effect of temperature and carbohydrates on glycogen, fatigue and performance? (Pitsiladis & Maughan 1999)
Protocol - high CHO cold (10C), low CHO cold, high CHO hot (30C) vs low CHO hot
Results
- glycogen depletion cause fatigue in the cold
- time to exhaustion is longer in the cold
118
The effect of the cold on sweat loss and fluid intake during exercise? (Maughan et al. 2005)
Protocol - football training in a range of temperatures
Results
- exercising in the cold reduces sweat loss and fluid intake
- dehydration was greater in the cold
119
The effect of temperature on fluid intake, sweat loss, thirst and serum osmolality when exercising? (Mears & Shirreffs 2014)
Protocol
- cycling for 1hr at 60% VOmax
- 0C vs 20C
Results
- increased fluid intake and sweat loss in the warm
- increased thirst in the warm
- no change in thirst in the cold despite the same exercise and reduced fluid intake
- serum osmolality has to be a lot higher to be able to stimulate thirst in the cold - blunted thirst response
120
The effect of acute altitude exposure on appetite? (Wasse et al. 2012)
Protocol
- 10 males
- rest vs exercise
- hypoxia vs normoxia
- 60min at 70% VO2max
- standardised meal at 2hrs and ad-lib buffet at 5.5hr
Results
- energy intake was similar between exercise and rested hypoxia
- energy intake was similar between exercise and rested normoxia
- energy intake was decreased in hypoxia when compared to normoxia
- ghrelin was suppressed in hypoxia
121
The effect of chronic and acute altitude on glucose utilisation and GLUT4? (Brooks et al. 1991)
Protocol
- 7 males
- sea level, chronic altitude or acute altitude
- labelled glucose infusion
- 90min rest, 45min @ 50% VO2max
Results
- acute altitude increased glucose utilisation during exercise
- chronic altitude increased glucose utilisation at rest and during exercise
- hypoxia increases expression of GLUT4
122
The effects of iron supplementation? (Govus et al. 2015)
Protocol - contol, 105mg or 210mg
Results
- when iron was ingested it stimulated hepcidin release
- total iron increases to a greater extent with 210mg
- iron supplementation increased haemoglobin mas by 3-4%
- splitting the dose enabled them to prevent a massive rise in hepcidin and further increased haemoglobin mass
