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Item Correction to: Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists(Springer Vienna, 2018-10) Kephart, Wesley C.; Wachs, Taylor D.; Mac Thompson, R.; Mobley, C. Brooks; Fox, Carlton D.; McDonald, James R.; Ferguson, Brian S.; Young, Kaelin C.; Nie, Ben; Martin, Jeffrey S.; Company, Joseph M.; Pascoe, David D.; Arnold, Robert D.; Moon, Jordan R.; Roberts, Michael D.Correction: The authors claim that their names were incorrectly listed on PubMed. For the author R. Mac Thompson, the first name should be R. Mac and the last name should be Thompson. On SpringerLink the name is listed correctly, but on PubMed he is listed as Mac Thompson R. For another author C. Brooks Mobley, the first name should be C. Brooks and the last name should be Mobley. On SpringerLink the name is listed correctly, but on PubMed he is listed as Brooks Mobley C.Item Site-specific associations of muscle thickness with bone mineral density in middle-aged and older men and women(Akadémiai Kiadó, 2016-06) Abe, Takashi; Loenneke, Jeremy P.; Young, Kaelin C.; Nahar, Vinayak K.; Hollaway, Kaitlyn M.; Stover, Caitlin D.; Ford, M. Allison; Bass, Martha A.; Owens, Scott G.; Loftin, MarkIt is unknown whether age-related site-specific muscle loss is associated with areal bone mineral density (aBMD) in older adults. To examine the relationships between aBMD and whole-body muscle thickness distribution, 97 healthy adults (46 women and 51 men) aged 50-78 years volunteered. Total and appendicular lean soft tissue mass, aBMD of the lumbar spine (LS-aBMD) and femoral neck (FN-aBMD) were determined using dual-energy X-ray absorptiometry. Muscle thickness (MT) was measured by ultrasound at nine sites of the body (forearm, upper arm, trunk, upper leg, and lower leg). Relationships of each co-variate with aBMD were tested partialling out the effect of age. aBMD was not correlated with either MT of the trunk or anterior lower leg in either sex. In men, significant and relatively strong correlations were observed between anterior and posterior upper arms, posterior lower leg, and anterior upper leg MT and LS-aBMD or FN-aBMD. In women, significant correlations were observed between anterior and posterior upper legs, posterior lower leg, and anterior upper arm MT and FN-aBMD. LS-aBMD was only correlated with forearm and posterior upper leg MT in women. In conclusion, the site-specific association of MT and aBMD differs between sexes and may be associated with the participants' daily physical activity profile.Item Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists(Springer Vienna, 2016-03) Kephart, Wesley C.; Wachs, Taylor D.; Mac Thompson, R.; Mobley, C. Brooks; Fox, Carlton D.; McDonald, James R.; Ferguson, Brian S.; Young, Kaelin C.; Nie, Ben; Martin, Jeffrey S.; Company, Joseph M.; Pascoe, David D.; Arnold, Robert D.; Moon, Jordan R.; Roberts, Michael D.We examined if supplementing trained cyclists (32 +/- A 2 year, 77.8 +/- A 2.6 kg, and 7.4 +/- A 1.2 year training) with 12 g/day (6 g/day l-Leucine, 2 g/day l-Isoleucine and 4 g/day l-Valine) of either branched-chain amino acids (BCAAs, n = 9) or a maltodextrin placebo (PLA, n = 9) over a 10-week training season affected select body composition, performance, and/or immune variables. Before and after the 10-week study, the following was assessed: (1) 4-h fasting blood draws; (2) dual X-ray absorptiometry body composition; (3) Wingate peak power tests; and (4) 4 km time-trials. No group x time interactions existed for total lean mass (P = 0.27) or dual-leg lean mass (P = 0.96). A significant interaction existed for body mass-normalized relative peak power (19 % increase in the BCAA group pre- to post-study, P = 0.01), and relative mean power (4 % increase in the BCAA group pre- to post-study, P = 0.01). 4 km time-trial time to completion approached a significant interaction (P = 0.08), as the BCAA group improved in this measure by 11 % pre- to post-study, though this was not significant (P = 0.15). There was a tendency for the BCAA group to present a greater post-study serum BCAA: l-Tryptophan ratio compared to the PLA group (P = 0.08). A significant interaction for neutrophil number existed (P = 0.04), as there was a significant 18 % increase within the PLA group from the pre- to post-study time point (P = 0.01). Chronic BCAA supplementation improves sprint performance variables in endurance cyclists. Additionally, given that BCAA supplementation blunted the neutrophil response to intense cycling training, BCAAs may benefit immune function during a prolonged cycling season.Item Influence of adipose tissue mass on DXA-derived lean soft tissue mass in middle-aged and older women(Springer International Publishing AG, 2015-01-30) Abe, Takashi; Patterson, Kaitlyn M.; Stover, Caitlin D.; Young, Kaelin C.The purpose of this study was to examine the influence of fat-free adipose tissue mass (FFAT) on association between dual-energy X-ray absorptiometry (DXA)-derived lean soft tissue mass and skeletal muscle mass (TMM). Forty-one middle-aged and older women were recruited for this study. Percent body fat, total and appendicular fat mass (tFM and aFM, respectively), and total and appendicular lean soft tissue mass (tLM and aLM, respectively) were measured using a DXA. FFAT was calculated based on the methods of a previous study. TMM was estimated from the ultrasound-derived prediction equation. The subjects were separated into three groups based on DXA-determined percent fat: low (n=12, <25 %), middle (n=15, >= 25 and <35 %), and high (n=14, >= 35 %). DXA-derived aLM was greater in high than in middle or low, although ultrasound-estimated TMM was similar among the three groups. There was a strong correlation between aLM and TMM (r=0.905, p<0.001). The difference between aLM and TMM was correlated (p<0.001) with aFM (r=0.599) and tFM (r=0.587). After adjusting for FFAT, aLM minus appendicular FFAT was similar among the three groups. aLM minus appendicular FFAT was strongly associated with TMM (r=0.912, p<0.001). Our results suggest that DXA-derived aLM accurately predicts TMM when subjects have moderate or lower adipose tissue mass. However, FFAT may falsely inflate the DXA-derived aLM measurement in individuals with a relatively high amount of adipose tissue mass (>35% of body fat). Therefore, in this population, it is advisable to use DXA-derived aLM minus FFAT when evaluating age-related loss of skeletal muscle mass.Item Validity of ultrasound prediction equations for total and regional muscularity in middle-aged and older men and women(Elsevier Science Inc., 2015-02) Abe, Takashi; Loenneke, Jeremy P.; Young, Kaelin C.; Thiebaud, Robert S.; Nahar, Vinayak K.; Hollaway, Kaitlyn M.; Stover, Caitlin D.; Ford, M. Allison; Bass, Martha A.; Loftin, MarkTo test the validity of published equations, 79 Caucasian adults (40 men and 39 women) aged 50-78 y had muscle thickness (MT) measured by ultrasound at nine sites of the body. Fat-free mass (FFM), lean soft tissue mass (LM) and total muscle mass (TMM) were estimated from MT using equations previously published in the literature. Appendicular LM (aLM) was estimated using dual-energy X-ray absorptiometry (DXA) and this method served as the reference criterion. There were strong correlations (range r = 0.85-0.94) between DXA-derived aLM and estimated FFM, leg LM or TMM. Total error between DXA-derived aLM and TMM (similar to 2 kg) was lower compared with the three other selected equations (6-10 kg). A Bland-Altman plot revealed that there was no systematic bias between aLM and TMM; however, the other three equations included systematic error. Our results suggest that an ultrasound equation for TMM is appropriate and useful for evaluating skeletal muscle mass in the body. (E-mail: t12abe@gmail.com) (C) 2015 World Federation for Ultrasound in Medicine & Biology.