Kinesiology

Navalta, J.W., and S.P. Hrncir Jr. Core stabilization exercises enhance lactate clearance following high-intensity exercise. J. Strength Cond. Res. 21(4): 1305-1309. 2007.-Dynamic activities such as running, cycling, and swimming have been shown to effectively reduce lactate in the postexercise period. It is unknown whether core stabilization exercises performed following an intense bout would exhibit a similar effect. Therefore, this study was designed to assess the extent of the lactate response with core stabilization exercises following high-intensity anaerobic exercise. Subjects (N ϭ 12) reported twice for testing, and on both occasions baseline lactate was obtained after 5 minutes of seated rest. Subjects then performed a 30-second Wingate anaerobic cycle test, immediately followed by a blood lactate sample. In the 5-minute postexercise period, subjects either rested quietly or performed core stabilization exercises. A final blood lactate sample was obtained following the 5-minute intervention period. Analysis revealed a significant interaction (p ϭ 0.05). Lactate values were similar at rest (core ϭ 1.4 Ϯ 0.1, rest ϭ 1.7 Ϯ 0.2 mmol·L Ϫ1 ) and immediately after exercise (core ϭ 4.9 Ϯ 0.6, rest ϭ 5.4 Ϯ 0.4 mmol·L Ϫ1 ). However, core stabilization exercises performed during the 5-minute postexercise period reduced lactate values when compared to rest (5.9 Ϯ 0.6 vs. 7.6 Ϯ 0.8 mmol·L Ϫ1 ). The results of this study show that performing core stabilization exercises during a recovery period significantly reduces lactate values. The reduction in lactate may be due to removal via increased blood flow or enhanced uptake into the core musculature. Incorporation of core stability exercises into a cool-down period following muscular work may result in benefits to both lactate clearance as well as enhanced postural control.

INDIVIDUALS. James W Navalta, Darlene A Sedlock, Kyung-Shin Park. JEPonline. 2004;7(6):45-51. The purpose of this study was to measure selected cardiovascular and metabolic responses in healthy older and younger individuals during downhill walking. Twenty subjects, ten older [age 64±3 yr (mean±SD)] and ten younger (age 23±3 yr) performed 6 min treadmill walking bouts at 80.4 m/min at grades of 5, 0, -5, -10, -15, and -20 %. Heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure, rate pressure product (RPP), oxygen uptake (VO 2 ), pulmonary ventilation (V E ), and rate of perceived exertion (RPE) were determined. Older subjects had significantly greater HR, SBP, RPP, DBP and RPE during uphill, level, and downhill walking compared to younger subjects. Older individuals exhibited similar VO 2 and V E during downhill walking compared with younger subjects. There was a characteristic curvilinear response observed for HR, SBP, RPP, VO 2 , and V E with progressively steeper negative grades. These measures were highest at 5% grade and lowest between -5% and -10%. Downhill walking at grades between -5% and -10% reduced the cardiovascular and metabolic demand during exercise in older and younger subjects. Downhill walking is an activity that may be particularly beneficial for older individuals who are previously sedentary and at the beginning stages of an exercise training program.

Int J Exerc Sci 3(1): [1][2][3] 2010. The popularity of the International Journal of Exercise Science continues to rise. As a student-focused journal, we are pleased to provide these future professionals with opportunities to gain experience with the peer review process, both through submitting their original work and as manuscript reviewers. Our editorial process is changing as section editors with specialties within the field of exercise science have agreed to take on these responsibilities. In addition, we are proud to also publish conference proceedings from various meetings held around the world. A list of individuals who have reviewed manuscripts throughout the last year is included.

Repetitive jumping has been identified as a possible exercise modality able to provide sufficient stimulus to improve bone health. However, it is necessary to establish whether repetitive jumping can elicit a consistent physiological response with the ablity to monitor work rate. The ...

The aim of the present study was to evaluate the acute effects of resistance exercise (RE) leading to failure and RE that was not to failure on 24 h blood pressure (BP) and heart rate variability (HRV) in sedentary normotensive adult women. Methods: Ten women (33.2 ± 5.8 years; 159.3 ± 9.4 cm; 58.0 ±6.4 kg; body fat 28.4 ± 2.8%) randomly underwent three experimental sessions: control (40 minutes of seated rest), RE leading to failure with 3 sets of 10 repetitions maximum (10-RM), and RE not to failure at 60% of 10-RM with 3 sets of 10 repetitions. Immediately post session BP and HRV were measured for 24 h.

To compare the metabolic parameters, flexibility, muscle strength, functional capacity, and lower limb muscle power of elderly women with and without the metabolic syndrome (MetS). Methods: This cross-sectional study included 28 older women divided into two groups: with the MetS (n = 14; 67.3 ± 5.5 years; 67.5 ± 16.7 kg; 1.45 ± 0.35 m; 28.0 ± 7.6 kg/m 2 ), and without the MetS (n = 14; 68.7 ± 5.3 years; 58.2 ± 9.9 kg; 1.55 ± 0.10 m; 24.3 ± 3.8 kg/m 2 ). Body composition was evaluated by dual-energy X-ray absorptiometry and dynamic muscle strength was assessed by one-maximum repetition (1RM) tests in leg press, bench press and biceps curl exercises. Six-minute walk test, Timed Up and Go (TUG); 30-second sitting-rising; arm curl using a 2-kg dumbbell, sit-and-reach (flexibility), and vertical jump tests were performed. Results: There was no difference between groups regarding age (P = 0.49), height (P = 0.46), body fat (%) (P = 0.19), systolic (P = 0.64), diastolic (P = 0.41) and mean blood pressure (P = 0.86), 30-second sitting-rising (P = 0.57), 30-s arm curl (P = 0.73), leg press 1RM (P = 0.51), bench press 1RM (P = 0.77), and biceps curl 1RM (P = 0.85). However, women without the MetS presented lower body mass (P = 0.001), body mass index (BMI) (P = 0.0001), waist circumference (P = 0.02), waist-to-height ratio (P = 0.02), fat body mass (kg) (P = 0.05), lean body mass (kg) (P = 0.02), blood glucose (P = 0.05), triglycerides (P = 0.03), Z-score for the MetS (P = 0.05), higher high-density lipoprotein-cholesterol (HDL-C) (P = 0.002), better performance on TUG (P = 0.01), flexibility (P = 0.03), six-minute walk test (P = 0.04), vertical jump (P = 0.05) and relative muscle strength for leg press (P = 0.03), bench press (P = 0.04) and biceps curl (P = 0.002) exercises as compared to women with the MetS. Conclusion: Elderly women with the MetS have higher metabolic risk profile and lower functional capacity, muscle strength, lower limb power and flexibility as compared to women without the MetS. The evaluation of functional capacity may help to determine the degree of physical decline in older persons with the MetS, while exercise interventions should be encouraged.

The purpose of the present study was to examine the effects of eight weeks of resistance training (RT) on anthropometric, cardiovascular and biochemical risk factors of metabolic syndrome (MetS), and neuromuscular variables on overweight/obese women.

Exercise modulates both glucose and glutamine metabolism which influences lymphocyte function. We investigated the influence of chronic moderate exercise on glucose and glutamine metabolism in lymphocytes, the associated influence on proliferation, and cytokine and immunoglobulin production. Male Wistar rats (8 weeks old) were placed in an exercise training group (N = 15, 1 h day -1 at 60 % VO 2max , 5 days week -1 ) for 8 weeks of exercise, or a sedentary control group. Twenty-four hours following the final training session, lymphocytes were separated, and the incorporation of [U-14C]-glucose, [U-14C]-glutamine, and [2-14C]-thymidine from the supernatant was measured. The activity of glucose-6-phosphate dehydrogenase, hexokinase, and glutaminase was measured. Lymphocytes were stimulated with ConA and LPS and incubated with the Mycobacterium bovis bacille Calmette-Guerin (BCG) vaccine and plasma IgG and IgE were measured. Glutamine metabolism increased in both T and B lymphocytes in the trained group. In the trained group, proliferative capacity increased T lymphocytes under ConA stimulation, and increased B lymphocytes with LPS. There was a significant increase in IL-2 production and decrease in IL-4 in the trained group compared with sedentary controls. IL-2R and TNFR increased in trained rats while IL-4R decreased and were more pronounced in T lymphocytes compared with B lymphocytes. In both lymphocyte subsets, exercise training significantly increased the expression of CD54? and CD30? cell markers. Exercise training increased plasma IgG compared with the sedentary group. In conclusion, moderate exercise training improves immune function and metabolism Communicated by William J. Kraemer.

The IL-6 gene polymorphism has been associated with disease prevalence and different physiological responses to exercise. Eccentric resistance exercise (ERE) is considered a nonpharmacological tool to prevent the chronic degenerative profile associated with aging and obesity. Consequently, the aim of the present study was to investigate the influence of IL-6 −174G/C polymorphism on acute interleukin-6 (IL-6) and creatine kinase (CK) temporal response to ERE in elderly obese women. Ninety women completed seven sets of ten repetitions (eccentric only) of an acute ERE session at 110% of the ten repetitions maximum (10RM). IL-6 genotypes displayed no difference at baseline. ERE induced changes in CK concentration over time occurred only in the GG group, F(2.619, 136.173) = 5.199, p = 0.003, with CK activity increased from 106.8 ± 6.9 U/l pre-intervention to 122.7 ± 11.2 U/l at 24 h and 131.9 ± 14.4 U/l at 48 h post-exercise. IL-6 concentration in the GG group was lower than the CC/CG group only at 0 h post-exercise (3.78 ± 0.58 pg/ml versus 6.51 ± 1.91 pg/ml, p = 0.030). Only the GG genotype group had higher CK activity 24-48 h following ERE and greater CK integral values, while IL-6 activity over 48 h was higher in the CC/CG genotype group. In conclusion, IL-6 genotype affects CK and IL-6 in response to ERE. It is of interest that the ERE protocol induced an elevation in CK, indicating possible muscle damage without exacerbating IL-6 and CK for the GG genotype.

The IL-6 gene polymorphism has been associated with disease prevalence and different physiological responses to exercise. Eccentric resistance exercise (ERE) is considered a nonpharmacological tool to prevent the chronic degenerative profile associated with aging and obesity. Consequently, the aim of the present study was to investigate the influence of IL-6 −174G/C polymorphism on acute interleukin-6 (IL-6) and creatine kinase (CK) temporal response to ERE in elderly obese women. Ninety women completed seven sets of ten repetitions (eccentric only) of an acute ERE session at 110% of the ten repetitions maximum (10RM). IL-6 genotypes displayed no difference at baseline. ERE induced changes in CK concentration over time occurred only in the GG group, F(2.619, 136.173) = 5.199, p = 0.003, with CK activity increased from 106.8 ± 6.9 U/l pre-intervention to 122.7 ± 11.2 U/l at 24 h and 131.9 ± 14.4 U/l at 48 h post-exercise. IL-6 concentration in the GG group was lower than the CC/CG group only at 0 h post-exercise (3.78 ± 0.58 pg/ml versus 6.51 ± 1.91 pg/ml, p = 0.030). Only the GG genotype group had higher CK activity 24-48 h following ERE and greater CK integral values, while IL-6 activity over 48 h was higher in the CC/CG genotype group. In conclusion, IL-6 genotype affects CK and IL-6 in response to ERE. It is of interest that the ERE protocol induced an elevation in CK, indicating possible muscle damage without exacerbating IL-6 and CK for the GG genotype.

The association of ageing with obesity commits elderly women and has been correlated with multiple degenerative processes, which could be occasioned by an enhancing in levels of matrix metalloproteinase-2 and metalloproteinase-9 (MMPs) as well by an cytokine unbalance that included an enhancing on interleukin-6 (IL-6). Furthermore, other factors could be also related to degenerative process, as they could be reduced by eccentric resistance exercise (ERE), which seems particularly important to initiate resistance training in obese older adults. In this view, this study aims to determinate the effects of an acute ERE session on serum MMP-2, MMP-9 and IL-6 in elderly obese women. Ten elderly obese women participated in this study and completed a 10 repetitions maximum test (10 RM) utilizing leg extension exercise. Subjects then completed an acute ERE session consisting of seven sets of 10 repetitions at 110% of 10 RM with a rest of 3 min between sets. Blood samples were collected before, immediately after, 3, 24 and 48 h following the ERE session. Zymograms were utilized to measure the MMP-2 and MMP-9 enzymes from all individuals. Moreover, IL-6 concentration was also determinated. After ERE session, MMP-2 and MMP-9 decreased, remaining significantly below baseline values after 48 h (P<0Á05). Although not statistically significant, there was a tendency for IL-6 to decrease 48 h after the ERE when compared with 3 h (P = 0Á06). An acute ERE session decreases MMP-9, MMP-2 and IL-6 in elderly obese women, possibly indicating a transient protection against the low grade inflammation present in this specific population.