Exercise in the fasted state facilitates fibre type‐specific intramyocellular lipid breakdown and stimulates glycogen resynthesis in humans

Bock, Katrien De; Richter, Erik A.; Russell, Aaron P.; Eijnde, Bert O.; Derave, Wim; Ramaekers, Monique; Koninckx, Erwin; Léger, Bertrand; Verhaeghe, Johan; Hespel, Peter

doi:10.1113/jphysiol.2005.083170

Cited by 116 publications

(200 citation statements)

References 65 publications

Supporting

Mentioning

177

Contrasting

Unclassified

Order By: Relevance

“…It is well documented that exercise in F, compared with exercise in conjunction with carbohydrate intake, stimulates the contribution of fat oxidation to ATP production in muscles (3,6,19,23). This elevated fat turnover rate is at least partly due to greater utilization of IMCL in type I muscle fibers (19).…”

Section: Discussionmentioning

confidence: 99%

“…At the same time, reduced liver glycogen content impairs glucoregulation (15, 16), which suppresses the input of blood-borne glucose in energy turnover. Thus during exercise in the fasted state (F), the rate of fat oxidation for a given submaximal exercise intensity is significantly increased (6,19). This is at least partly due to enhanced degradation of intramyocellular lipids (IMCL) in type I muscle fibers (19).…”

mentioning

confidence: 99%

“…Muscle lysate production and Western blotting were done as previously described (19). The primary antibodies used were AMP-activated protein kinase ␣ (AMPK␣; Cell Signaling Technology, Danvers, MA), phospho-AMPK␣ Thr 172 (Cell Signaling Technology), acetyl-CoA carboxylase ␤ (ACC␤; Cell Signaling Technology), and phospho-ACC␤ Ser 221 (Cell Signaling Technology).…”

Section: Biochemical Analysesmentioning

confidence: 99%

“…The elevated plasma adrenaline-to-insulin ratio, due to fasting, increases circulating FFA concentration via stimulation of peripheral lipolysis (3,19,23). At the same time, reduced liver glycogen content impairs glucoregulation (15, 16), which suppresses the input of blood-borne glucose in energy turnover.…”

mentioning

confidence: 99%

“…Thus during exercise in the fasted state (F), the rate of fat oxidation for a given submaximal exercise intensity is significantly increased (6,19). This is at least partly due to enhanced degradation of intramyocellular lipids (IMCL) in type I muscle fibers (19). We also demonstrated that consistent training in F can increase membrane-bound fatty acidbinding protein and FAT/CD36 protein content in muscles more than an identical training program with ample carbohydrate intake (CHO) during the training sessions (16a).…”

mentioning

confidence: 99%

See 4 more Smart Citations

High-fat diet overrules the effects of training on fiber-specific intramyocellular lipid utilization during exercise

Proeyen

Szlufcik

Nielens

et al. 2011

Journal of Applied Physiology

View full text Add to dashboard Cite

Van Proeyen K, Szlufcik K, Nielens H, Deldicque L, Van Dyck R, Ramaekers M, Hespel P. High-fat diet overrules the effects of training on fiber-specific intramyocellular lipid utilization during exercise. J Appl Physiol 111: 108 -116, 2011. First published May 5, 2011 doi:10.1152/japplphysiol.01459.2010In this study, we compared the effects of endurance training in the fasted state (F) vs. the fed state [ample carbohydrate intake (CHO)] on exercise-induced intramyocellular lipid (IMCL) and glycogen utilization during a 6-wk period of a hypercaloric (ϳϩ30% kcal/day) fat-rich diet (HFD; 50% of kcal). Healthy male volunteers (18 -25 yrs) received a HFD in conjunction with endurance training (four times, 60 -90 min/wk) either in F (n ϭ 10) or with CHO before and during exercise sessions (n ϭ 10). The control group (n ϭ 7) received a HFD without training and increased body weight by ϳ3 kg (P Ͻ 0.001). Before and after a HFD, the subjects performed a 2-h constant-load bicycle exercise test in F at ϳ70% maximal oxygen uptake rate. A HFD, both in the absence (F) or presence (CHO) of training, elevated basal IMCL content by ϳ50% in type I and by ϳ75% in type IIa fibers (P Ͻ 0.05). Independent of training in F or CHO, a HFD, as such, stimulated exercise-induced net IMCL breakdown by approximately twofold in type I and by approximately fourfold in type IIa fibers. Furthermore, exercise-induced net muscle glycogen breakdown was not significantly affected by a HFD. It is concluded that a HFD stimulates net IMCL degradation by increasing basal IMCL content during exercise in type I and especially IIa fibers. Furthermore, a hypercaloric HFD provides adequate amounts of carbohydrates to maintain high muscle glycogen content during training and does not impair exercise-induced muscle glycogen breakdown. skeletal muscle; fasted exercise; fat-rich feeding; energy substrate metabolism; muscle lipids IT IS WELL ESTABLISHED THAT dietary factors play an important role in modulating the acute and chronic metabolic responses to endurance exercise (30). In this regard, increased preexercise dietary fat supply stimulates energy provision via fat oxidation during exercise (8,33). By analogy, fatty acid infusion elevates the input of free fatty acids (FFAs) in the energy substrate mix fueling muscle contractions (22, 48a, 49). Furthermore, chronic exposure to a high-fat diet (HFD) also enhances the use of FFAs in endurance exercise (8,9,25,29,(32)(33)(34)58). This is, at least partly, due to upregulation of rate-limiting steps in fat metabolic pathways. Thus FFA oxidation can be stimulated with appropriate chronic exercise and/or nutrition (e.g., HFD), which upregulates pivotal steps in FFA catabolism such as fatty acid translocase (FAT)/CD36 (4, 9), ␤-hydroxyacyl CoA dehydrogenase (␤-HAD) (9, 31), and hormone-sensitive lipase (HSL) (58). However, it is still unclear whether these adaptations are specifically due to the increased FFA supply per se or result from decreased glucose availability. Omission of glucose ingestion during exercise a...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Section: Biochemical Analysesmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

High-fat diet overrules the effects of training on fiber-specific intramyocellular lipid utilization during exercise

Proeyen

Szlufcik

Nielens

et al. 2011

Journal of Applied Physiology

View full text Add to dashboard Cite

show abstract

Distance Running

Stellingwerff

2013

The Encyclopaedia of Sports Medicine

View full text Add to dashboard Cite

Vertical Clinging and Leaping Ahead: How Bamboo Has Shaped the Anatomy and Physiology of Hapalemur

Hemingway

Burrows

Omstead

et al. 2019

The Anatomical Record

View full text Add to dashboard Cite

Hapalemur sps. and Prolemur simus (bamboo lemurs, collectively) stand out from the relatively homogeneous lemurids because they are bamboo feeders and vertical clingers and leapers. This unique diet presents equally unique challenges, like its verticality, toughness, and toxicity. The bamboo lemurs share the generalized anatomy of the other lemurids, but also display some well-documented skeletal adaptations, perhaps to overcome the problems presented by their specialization. Soft-tissue adaptations, however, remain largely unexplored. Explored here are possible soft-tissue adaptations in Hapalemur griseus. We compare H. griseus with other lemurids, Propithecus, Galago, Tarsier, and a tree shrew. Based on the available anatomical and physiological data, we hypothesize that Hapalemur and Prolemur species will have differences in hindlimb morphology when compared with other lemurids. We predict that H. griseus will have more hindlimb muscle mass and will amplify muscle mass differences with increased type II muscle fibers. Relative hindlimb muscle mass in H. griseus is less than other prosimians sampled, yet relative sural muscle mass is significantly heavier (P < 0.01) in H. griseus. Results show that the soleus muscle of H. griseus has a higher amount of type II (fast) fibers in plantarflexors. These findings indicate although H. griseus shares some generalized lemurid morphology, its diet of bamboo may have pushed this generalized lemurid to an anatomical extreme. We suspect additional bamboospecific adaptations in their anatomy and physiology will be uncovered with further examination into the anatomy of the bamboo lemurs.

show abstract

Exercise in the fasted state facilitates fibre type‐specific intramyocellular lipid breakdown and stimulates glycogen resynthesis in humans

Cited by 116 publications

References 65 publications

High-fat diet overrules the effects of training on fiber-specific intramyocellular lipid utilization during exercise

High-fat diet overrules the effects of training on fiber-specific intramyocellular lipid utilization during exercise

Distance Running

Vertical Clinging and Leaping Ahead: How Bamboo Has Shaped the Anatomy and Physiology of Hapalemur

Contact Info

Product

Resources

About