Biology subjects

Mangine, G.

Publications and source records attributed to Mangine, G..

2 recordsLinked to original sources

bioRxiv2019

PHYSIOLOGICAL DIFFERENCES BETWEEN ADVANCED CROSSFIT ATHLETES, RECREATIONAL CROSSFIT PARTICIPANTS, AND PHYSICALLY-ACTIVE ADULTS

This investigation examined anthropometric, hormonal, and physiological differences between advanced (ADV; n = 8, 27.8 {+/-} 4.2 years, 170 {+/-} 11 cm, 79.8 {+/-} 13.3 kg) and recreational (REC; n = 8, 33.5 {+/-} 8.1 years, 172 {+/-} 14 cm, 76.3 {+/-} 19.5 kg) CrossFit (CF) trained participants in comparison to physically-active controls (CON; n = 7, 27.5 {+/-} 6.7 years, 171 {+/-} 14 cm, 74.5 {+/-} 14.3 kg). ADV and REC were distinguished by their past competitive success. REC and CON were resistance-trained (>2 years) and exercised on 3-5 days{middle dot}wk-1 for the past year, but CON utilized traditional resistance and cardiovascular exercise. All participants provided a fasted, resting blood sample and completed assessments of resting metabolic rate, body composition, muscle morphology, isometric mid-thigh pull strength, peak aerobic capacity, and a 3-minute maximal cycle ergometer sprint across two separate occasions (separated by 3-7 days). Blood samples were analyzed for testosterone, cortisol, and insulin-like growth factor-1. One-way analysis of variance revealed ADV to possess lower body fat percentage (6.7-8.3%, p = 0.007), greater bone and non-bone lean mass (12.5-26.8%, p [≤] 0.028), muscle morphology characteristics (14.2-59.9%, p < 0.05), isometric strength characteristics (15.4-41.8%, p < 0.05), peak aerobic capacity (18.8-19.1%, p = 0.002), and anaerobic performance (15.4-51.1%, p [≤] 0.023) compared to both REC and CON. No differences were seen between REC and CON, or between all groups for resting metabolic rate or hormone concentrations. These data suggest ADV possess several physiological advantages over REC and CON, whereas similar physiological characteristics were present in individuals who have been regularly participating in either CF or resistance and cardiovascular training for the past year.

physiology↗

bioRxiv2018

RESISTANCE TRAINING DOES NOT INDUCE UNIFORM ADAPTATIONS TO QUADRICEPS MUSCLES

Resistance training may differentially affect morphological adaptations along the length of uni-articular and bi-articular muscles. The purpose of this study was to compare changes in muscle morphology along the length of the rectus femoris (RF) and vastus lateralis (VL) in response to resistance training. Following a 2-wk preparatory phase, 15 resistance-trained men (24.0 {+/-} 3.0 y, 90.0 {+/-} 13.8 kg, 174.9 {+/-} 20.7 cm) completed pre-training (PRE) assessments of muscle thickness (MT), pennation angle (PA), cross-sectional area (CSA), and echo-intensity in the RF and VL at 30, 50, and 70% of each muscles length; fascicle length (FL) was estimated from respective measurements of MT and PA within each muscle and region. Participants then began a high intensity, low volume (4 x 3 - 5 repetitions, 3min rest) lower-body resistance training program, and repeated all PRE-assessments after 8 weeks (2 d {middle dot} wk-1) of training (POST). Although three-way (muscle [RF, VL] x region [30, 50, 70%] x time [PRE, POST]) repeated measures analysis of variance did not reveal significant interactions for any assessment of morphology, significant simple (muscle x time) effects were observed for CSA (p = 0.002) and FL (p = 0.016). Specifically, average CSA changes favored the VL (2.96 {+/-} 0.69 cm2, pp < 0.001) over the RF (0.59 {+/-} 0.20 cm2, p = 0.011), while significant decreases in average FL were noted for the RF (-1.03 {+/-} 0.30 cm, p = 0.004) but not the VL (-0.05 {+/-} 0.36 cm, p = 0.901). No other significant differences were observed. The findings of this study demonstrate the occurrence of non-homogenous adaptations in RF and VL muscle size and architecture following 8 weeks of high-intensity resistance training in resistance-trained men. However, training does not appear to influence region-specific adaptations in either muscle.

physiology↗