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Physiological comparison of concentric and eccentric arm cycling in males and females.

Beaven CM, Willis SJ, Cook CJ, Holmberg HC - PLoS ONE (2014)

Bottom Line: In contrast, delta efficiency (ηΔ), as previously defined by Coyle and colleagues in 1992, demonstrated a sex difference (men>women; p<0.05).Sex differences were also apparent in arteriovenous oxygen difference and heart rate during CON.We suggest delta efficiency as a sensitive measure of efficiency that allowed the identification of sex differences.

View Article: PubMed Central - PubMed

Affiliation: Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.

ABSTRACT
Lower body eccentric exercise is well known to elicit high levels of muscular force with relatively low cardiovascular and metabolic strain. As a result, eccentric exercise has been successfully utilised as an adaptive stressor to improve lower body muscle function in populations ranging from the frail and debilitated, to highly-trained individuals. Here we investigate the metabolic, cardiorespiratory, and energy costs of upper body eccentric exercise in a healthy population. Seven men and seven women performed 4-min efforts of eccentric (ECC) or concentric (CON) arm cycling on a novel arm ergometer at workloads corresponding to 40, 60, and 80% of their peak workload as assessed in an incremental concentric trial. The heart rate, ventilation, cardiac output, respiratory exchange ratio, and blood lactate concentrations were all clearly greater in CON condition at all of the relative workloads (all p<0.003). Effect size calculations demonstrated that the magnitude of the differences in VO2 and work economy between the ECC and CON exercise ranged from very large to extremely large; however, in no case did mechanical efficiency (η(MECH)) differ between the conditions (all p>0.05). In contrast, delta efficiency (ηΔ), as previously defined by Coyle and colleagues in 1992, demonstrated a sex difference (men>women; p<0.05). Sex differences were also apparent in arteriovenous oxygen difference and heart rate during CON. Here, we reinforce the high-force, low cost attributes of eccentric exercise which can be generalised to the muscles of the upper body. Upper body eccentric exercise is likely to form a useful adjunct in debilitative, rehabilitative, and adaptive clinical exercise programs; however, reports of a shift towards an oxidative phenotype should be taken into consideration by power athletes. We suggest delta efficiency as a sensitive measure of efficiency that allowed the identification of sex differences.

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Energy cost of eccentric and concentric arm cycling.Values are reported as mean ± standard deviation. *p<0.05 vs concentric exercise modality. Horizontal bars represent significant differences between the indicated workloads p<0.05.
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pone-0112079-g002: Energy cost of eccentric and concentric arm cycling.Values are reported as mean ± standard deviation. *p<0.05 vs concentric exercise modality. Horizontal bars represent significant differences between the indicated workloads p<0.05.

Mentions: Extremely large or very large differences in VO2 were observed between the CON and ECC conditions at 40 (ES: 3.62±0.63; p<0.0001), 60 (ES: 4.16±0.63; p<0.0001), and 80% of WPEAK (ES: 4.08±0.63; p<0.0001; Figure 2A). VO2 consistently increased as workload increased in both conditions (all p<0.004). The qualitative magnitudes of the differences in economy (all ES >3.83), and ηMECH (all ES >3.83) between the CON and ECC conditions were either very large or extremely large (Figure 2B & 2C). In no case did ηMECH differ at the different workloads (all p>0.05; Figure 2C). It was noteworthy that a clear sex difference of 1.7±1.7% (ES: 0.95) in concentric ηΔ was observed (men>women), that was not apparent in the ηMECH metrics (Figure 3).


Physiological comparison of concentric and eccentric arm cycling in males and females.

Beaven CM, Willis SJ, Cook CJ, Holmberg HC - PLoS ONE (2014)

Energy cost of eccentric and concentric arm cycling.Values are reported as mean ± standard deviation. *p<0.05 vs concentric exercise modality. Horizontal bars represent significant differences between the indicated workloads p<0.05.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4221259&req=5

pone-0112079-g002: Energy cost of eccentric and concentric arm cycling.Values are reported as mean ± standard deviation. *p<0.05 vs concentric exercise modality. Horizontal bars represent significant differences between the indicated workloads p<0.05.
Mentions: Extremely large or very large differences in VO2 were observed between the CON and ECC conditions at 40 (ES: 3.62±0.63; p<0.0001), 60 (ES: 4.16±0.63; p<0.0001), and 80% of WPEAK (ES: 4.08±0.63; p<0.0001; Figure 2A). VO2 consistently increased as workload increased in both conditions (all p<0.004). The qualitative magnitudes of the differences in economy (all ES >3.83), and ηMECH (all ES >3.83) between the CON and ECC conditions were either very large or extremely large (Figure 2B & 2C). In no case did ηMECH differ at the different workloads (all p>0.05; Figure 2C). It was noteworthy that a clear sex difference of 1.7±1.7% (ES: 0.95) in concentric ηΔ was observed (men>women), that was not apparent in the ηMECH metrics (Figure 3).

Bottom Line: In contrast, delta efficiency (ηΔ), as previously defined by Coyle and colleagues in 1992, demonstrated a sex difference (men>women; p<0.05).Sex differences were also apparent in arteriovenous oxygen difference and heart rate during CON.We suggest delta efficiency as a sensitive measure of efficiency that allowed the identification of sex differences.

View Article: PubMed Central - PubMed

Affiliation: Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.

ABSTRACT
Lower body eccentric exercise is well known to elicit high levels of muscular force with relatively low cardiovascular and metabolic strain. As a result, eccentric exercise has been successfully utilised as an adaptive stressor to improve lower body muscle function in populations ranging from the frail and debilitated, to highly-trained individuals. Here we investigate the metabolic, cardiorespiratory, and energy costs of upper body eccentric exercise in a healthy population. Seven men and seven women performed 4-min efforts of eccentric (ECC) or concentric (CON) arm cycling on a novel arm ergometer at workloads corresponding to 40, 60, and 80% of their peak workload as assessed in an incremental concentric trial. The heart rate, ventilation, cardiac output, respiratory exchange ratio, and blood lactate concentrations were all clearly greater in CON condition at all of the relative workloads (all p<0.003). Effect size calculations demonstrated that the magnitude of the differences in VO2 and work economy between the ECC and CON exercise ranged from very large to extremely large; however, in no case did mechanical efficiency (η(MECH)) differ between the conditions (all p>0.05). In contrast, delta efficiency (ηΔ), as previously defined by Coyle and colleagues in 1992, demonstrated a sex difference (men>women; p<0.05). Sex differences were also apparent in arteriovenous oxygen difference and heart rate during CON. Here, we reinforce the high-force, low cost attributes of eccentric exercise which can be generalised to the muscles of the upper body. Upper body eccentric exercise is likely to form a useful adjunct in debilitative, rehabilitative, and adaptive clinical exercise programs; however, reports of a shift towards an oxidative phenotype should be taken into consideration by power athletes. We suggest delta efficiency as a sensitive measure of efficiency that allowed the identification of sex differences.

Show MeSH
Related in: MedlinePlus