scholarly journals Echinochrome A Improves Exercise Capacity during Short-Term Endurance Training in Rats

Marine Drugs ◽  
2015 ◽  
Vol 13 (9) ◽  
pp. 5722-5731 ◽  
Author(s):  
Dae Seo ◽  
Robin McGregor ◽  
Su Noh ◽  
Seung Choi ◽  
Natalia Mishchenko ◽  
...  
2017 ◽  
Vol 122 (1) ◽  
pp. 48-59 ◽  
Author(s):  
Casper Skovgaard ◽  
Nicki Winfield Almquist ◽  
Jens Bangsbo

The aim of the study was, in runners accustomed to speed endurance training (SET), to examine the effect of increased and maintained frequency of SET on performance and muscular adaptations. After familiarization (FAM) to SET, 18 male ( n = 14) and female ( n = 4) runners (V̇o2max: 57.3 ± 3.4 ml/min; means ± SD) completed 20 sessions of maintained low-frequency (LF; every fourth day; n = 7) or high-frequency (HF; every second day; n = 11) SET. Before FAM as well as before and after an intervention period (INT), subjects completed a series of running tests and a biopsy from m. vastus lateralis was collected. Ten-kilometer performance improved ( P < 0.05) ~3.5% during FAM with no further change during INT. Time to exhaustion at 90% vV̇o2max was 15 and 22% longer ( P < 0.05) during FAM and a further 12 and 16% longer ( P < 0.05) during INT in HF and LF, respectively. During FAM, muscle expression of NHE1 and maximal activity of citrate synthase (CS) and phosphofructokinase (PFK) increased ( P < 0.05), running economy (RE) improved ( P < 0.05), and V̇o2max was unchanged. During INT, both HF and LF increased ( P < 0.05) muscle expression of NKAβ1, whereas maximal activity of CS and PFK, RE, and V̇o2max were unchanged. Furthermore, during INT, muscle expression of FXYD1 and SERCA1, and FXYD1 activity increased ( P < 0.05) in HF, while muscle expression of SERCA2 decreased ( P < 0.05) in LF. Thus increased or maintained frequency of SET leads to further improvements in short-term exercise capacity, but not in 10-km running performance. The better short-term exercise capacity may be associated with elevated expression of muscle proteins related to Na+/K+ transportation and Ca2+ reuptake. NEW & NOTEWORTHY Ten speed endurance training (SET) sessions improved short-term exercise capacity and 10-km performance, which was followed by further improved short-term exercise capacity, but unchanged 10-km performance after 20 SET sessions performed with either high frequency (4 per 8 days) or continued low frequency (2 per 8 days) in trained runners. The further gain in short-term exercise capacity was associated with changes in muscle expression of proteins of importance for the development of fatigue.


1996 ◽  
Vol 270 (2) ◽  
pp. E328-E335 ◽  
Author(s):  
A. Chesley ◽  
G. J. Heigenhauser ◽  
L. L. Spriet

The purpose of this study was to examine the regulation (hormonal, substrate, and allosteric) of muscle glycogen phosphorylase (Phos) activity and glycogenolysis after short-term endurance training. Eight untrained males completed 6 days of cycle exercise (2 h/day) at 65% of maximal O2 uptake (Vo2max). Before and after training subjects cycled for 15 min at 80% of Vo2max, and muscle biopsies and blood samples were obtained at 0 and 30 s, 7.5 and 15 min, and 0, 5, 10, and 15 min of exercise. Vo2max was unchanged with training but citrate synthase (CS) activity increased by 20%. Muscle glycogenolysis was reduced by 42% during the 15-min exercise challenge following training (198.8 +/- 36.9 vs. 115.4 +/- 25.1 mmol/kg dry muscle), and plasma epinephrine was blunted at 15 min of exercise. The Phos a mole fraction was unaffected by training. Muscle phosphocreatine utilization and free Pi and AMP accumulations were reduced with training at 7.5 and 15 min of exercise. It is concluded that posttransformational control of Phos, exerted by reductions in substrate (free Pi) and allosteric modulator (free AMP) contents, is responsible for a blunted muscle glycogenolysis after 6 days of endurance training. The increase in CS activity suggests that the reduction of muscle glycogenolysis was due in part to an enhanced mitochondrial potential.


2012 ◽  
Vol 9 (3) ◽  
pp. 153-162 ◽  
Author(s):  
Zoe J McKeough ◽  
Peter TP Bye ◽  
Jennifer A Alison

The aim of this study was to compare the effects of arm endurance training, arm strength training, a combination of arm endurance and strength training, and no arm training on endurance arm exercise capacity. A randomised controlled trial was undertaken with chronic obstructive pulmonary disease subjects randomised into one of four groups to complete 8 weeks of training: (a) arm endurance training (endurance group) consisting of supported and unsupported arm exercises, (b) arm strength training (strength group) using weight machines, (c) a combination of arm endurance and arm strength training (combined group), or (d) no arm training (control group). The primary outcome measurement was endurance arm exercise capacity measured by an endurance arm crank test. Secondary outcomes included functional arm exercise capacity measured by the incremental unsupported arm exercise test and health-related quality of life. A total of 52 subjects were recruited and 38 (73%) completed the study. When comparing the arm endurance group to the control group, there was a significant increase in endurance time of 6 min (95% CI 2–10, p < 0.01) following the interventions. When comparing the combined group to each of the control, endurance and strength groups, there was a significantly greater reduction in dyspnoea and rate of perceived exertion at the end of the functional arm exercise test for the combined group following the interventions. The mode of training to be favoured to increase endurance arm exercise capacity is arm endurance training. However, combined arm endurance and strength training may also be very useful to reduce the symptoms during everyday arm tasks.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0261723
Author(s):  
Jamie-Lee M. Thompson ◽  
Daniel W. D. West ◽  
Thomas M. Doering ◽  
Boris P. Budiono ◽  
Sarah J. Lessard ◽  
...  

Skeletal muscle atrophy is a physiological response to disuse, aging, and disease. We compared changes in muscle mass and the transcriptome profile after short-term immobilization in a divergent model of high and low responders to endurance training to identify biological processes associated with the early atrophy response. Female rats selectively bred for high response to endurance training (HRT) and low response to endurance training (LRT; n = 6/group; generation 19) underwent 3 day hindlimb cast immobilization to compare atrophy of plantaris and soleus muscles with line-matched controls (n = 6/group). RNA sequencing was utilized to identify Gene Ontology Biological Processes with differential gene set enrichment. Aerobic training performed prior to the intervention showed HRT improved running distance (+60.6 ± 29.6%), while LRT were unchanged (-0.3 ± 13.3%). Soleus atrophy was greater in LRT vs. HRT (-9.0 ±8.8 vs. 6.2 ±8.2%; P<0.05) and there was a similar trend in plantaris (-16.4 ±5.6% vs. -8.5 ±7.4%; P = 0.064). A total of 140 and 118 biological processes were differentially enriched in plantaris and soleus muscles, respectively. Soleus muscle exhibited divergent LRT and HRT responses in processes including autophagy and immune response. In plantaris, processes associated with protein ubiquitination, as well as the atrogenes (Trim63 and Fbxo32), were more positively enriched in LRT. Overall, LRT demonstrate exacerbated atrophy compared to HRT, associated with differential gene enrichments of biological processes. This indicates that genetic factors that result in divergent adaptations to endurance exercise, may also regulate biological processes associated with short-term muscle unloading.


Sign in / Sign up

Export Citation Format

Share Document