David J. Lantis

Assessment, Consequence, and Clinical Implication of Asymmetry

Abstract The etiology of multiple sclerosis (MS) is complex, unpredictable, and unsystematic nerve demyelination, axonal deterioration, and neuroaxonal loss. Consequently, MS impairs the ability to transmit neurological signals throughout ones nervous system. The implications of nerve transmission disturbances include, but are not limited to, a multitude of functional symptoms such as abnormal gait, deficient balance, muscle weakness, spasticity, foot drop, and fatigue. Furthermore, the pathophysiology of MS can generate asymmetrical effects where one side of the body has more severe functional impairments. It follows that these bilateral differences have significant clinical importance. Nevertheless, bilateral asymmetry has yet to be comprehensively quantified. Additionally, the lack of knowledge about the impact asymmetry has on activities of daily living, quality of life, and exercise tolerance creates challenges for the prescription and implementation of rehabilitation.

Eight Weeks of High-Volume Resistance Training Improves Onset of Blood Lactate in Trained Individuals

Abstract Lantis, DJ, Farrell, JW, III, Cantrell, GS, and Larson, RD. Eight weeks of high volume resistance training improves onset of blood lactate in trained individuals. J Strength Cond Res 31(8): 2176–2182, 2017—The purpose of this study was to determine if onset of blood lactate (OBLA) using the fixed at 4 mmol·L−1 method could be delayed by supplementing high-volume resistance training (HVRT) to existing endurance training programs. There were 20 male subjects who participated in the study; 11 experimental (EX) (22.8 ± 4.6 years) and 9 controls (CON) (23.2 ± 5.8 years). An incremental cycling test was performed to determine maximal oxygen uptake, OBLA, maximum power, and time to exhaustion. Additionally, strength of the leg press (LP), leg curl (LC), and leg extension (LE) was assessed in both groups. Participants continued their ongoing endurance training, whereas the EX group supplemented their training with HVRT twice weekly for 8 weeks, performing 4 sets of 15 repetitions of LP, LC, and LE. Change score (post–pre) analysis was measured, using t-tests to compare the differences between groups, to eliminate outside variables that may have affected testing performance. Significance was set at p ⩽ 0.05. No significant group differences in baseline measures were observed. A significant difference was observed for OBLA at 4 mmol·L−1 (EX: 18.17 ± 15.36 W and CON: −3.52 ± 20.13 W, p < 0.02). A significant difference was observed for LP (EX: 39.09 ± 25.87 kg and CON: 4.22 ± 34.65 kg, p < 0.02) and LC (EX: 22.84 ± 8.7 kg and CON: −1.47 ± 8.2 kg, p < 0.01). Supplementing HVRT in endurance-trained individuals delayed OBLA at 4 mmol·L−1 and improved leg strength. The HVRT used in the current study may be a useful training style for endurance-trained individuals.