This investigation assessed the lymphocyte subset response to increasing intensity. Participants completed an exertion test (VO(2max)), and later performed a 10-min run at 76% VO(2max), 5-min at 87%, and run to exhaustion at 100% intensity. Blood was sampled at rest, following each intensity, and 1-h post. Cell concentration, apoptosis (annexin V) and migration (CX₃CR1) were evaluated in CD4+, CD8+, and CD19+ subsets. Relative data were analyzed using 1-way ANOVA with significance at P≤0.05. Absolute changes from rest (Δ baseline) were calculated for exercise conditions. CX₃CR1 displayed relative changes 1-h post, (CD8+ Pre=58%, Post=68%, 1 h-Post=37%, P=0.04) (CD19+ Pre=1.9%, Post=3.2%, 1 h-Post=5.2%, P=0.02). No relative changes were noted for subsets and annexin V. Absolute changes revealed that CD4+/annexin V+ and CD8+/annexin V+ significantly increased at 76%,(P<0.01). Significant absolute increases were observed in CD4+/CX₃CR1 at 87% VO2max, and at 87% and 100% VO2max in CD8+/CX₃CR1 (P<0.01). Subsets respond differently with intensity with respect to cell count, and markers of apoptosis and cell migration. CD4+ and CD8+ appear to be prone to apoptosis with moderate exercise, but significant increases in migration at higher intensities suggests movement of these cells from the vasculature in postexercise measurements.
Studies have shown significant changes in lymphocytes during continuous exercise, but little has been shown on the effect of repeated high intensity bouts. This study was designed to examine the effect of repeated intermittent bouts on lymphocyte subset cell count, apoptosis, and migration. A series of 6 Wingate anaerobic cycle tests were performed by participants (N = 8) with blood samples attained before, immediately following, and after a designated recovery period (excess postexercise oxygen consumption (EPOC)) to observe lymphocyte changes. Lymphocyte subsets (CD4+, CD4/CD45RA+, CD8+, CD8+/CD45RA+, CD19+) were assessed for apoptosis (annexin V+) and cellular migration (CX(3)CR1). Our results indicate that the CD8+ and CD8+/CD45RA+ subsets were significantly influenced by the repetitive Wingate cycling protocol such that cell counts increased with exercise, and then decreased at EPOC termination (p = 0.016). The observed postexercise decrease in CD8+ and CD8+/CD45RA+ cells was accompanied by a significant change in the CX(3)CR1 cell migration receptor (p = 0.019), but not apoptosis (p = 0.87). This indicates that with repetitive high-intensity cycling, the response in CD8+ cells following the bout is likely due to cell migration rather than cell death.
Statistical analyses (tests of probability) of judges' scores for various segments of Olympic skating performances in 1984 and 1988 indicate the presence of national bias. Judges rate skaters of their own nationality above the average of the remaining judges. They tend to give skaters of their own nationality the maximum score (among the judges), and their over-all rank for these skaters tends to be higher than the skaters' final Olympic standings. The authors suggest the possible use of trimmed means as one method of minimizing the effects of such bias.
High intensity functional training (HIFT) emphasizes constantly varied, high intensity, functional activity by programming strength and conditioning exercises, gymnastics, Olympic weightlifting, and specialty movements. Conversely, traditional circuit training (TCT) programs aim to improve muscular fitness by utilizing the progressive overload principle, similar movements weekly, and specified work-to-rest ratios. The purpose of this investigation was to determine if differences exist in health and performance measures in women participating in HIFT or TCT after a six-week training program. Recreationally active women were randomly assigned to a HIFT (n = 8, age 26.0 + 7.3 yrs) or TCT (n = 11, age 26.3 + 9.6 yrs) group. Participants trained three days a week for six weeks with certified trainers. Investigators examined body composition (BC), aerobic and anaerobic capacity, muscular strength, endurance, flexibility, power, and agility. Repeated-measures ANOVA were used for statistical analyses with an alpha level of 0.05. Both groups increased body mass (p = .011), and improved muscular endurance (p < .000), upper body strength (p = .007), lower body power (p = .029) and agility (p = .003). In addition, the HIFT group decreased body fat (BF) %, while the TCT group increased BF% (p = .011). No changes were observed in aerobic or anaerobic capacity, flexibility, upper body power, or lower body stair climbing power. Newer, high intensity functional exercise programs such as HIFT may have better results on BC and similar effects when compared with TCT programs on health and fitness variables such as musculoskeletal strength and performance.
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