A Comparison of Methods Used to Determine Percent Body Fat, Minimum Wrestling Weight, and Lowest Allowable Weight Class.

ABSTRACT: Cutrufello, PT, Landram, MJ, Venezia, AC, and Dixon, CB. A comparison of methods used to determine percent body fat, minimum wrestling weight, and lowest allowable weight class. J Strength Cond Res 35(3): 633-637, 2021-The National Collegiate Athletic Association's weight management program allows for the use of skinfold measurements (SF), air displacement plethysmography (ADP), and hydrostatic weighing in the assessment of percent body fat (%BF) and determination of a wrestler's minimum wrestling weight (MWW). Dual energy x-ray absorptiometry (DXA) and ultrasound (US) may offer alternative assessment methods. The purpose of this study was to examine %BF, MWW, and the lowest allowable weight class as determined by SF, ADP, DXA, and US. Thirty-three college-aged men (20.8 ± 1.1 years) participated. Urine specific gravity (Usg) was assessed to ensure proper hydration (1.006 ± 0.006). Percent body fat and MWW were then determined using the 4 assessment methods. Each method was significantly different from one another (p < 0.05) with the exception of ADP compared with SF (17.6 ± 7.1% vs. 17.4 ± 6.3%, p = 1.000) and DXA compared with US (20.5 ± 6.2% vs. 19.2 ± 7.5%, p = 0.124). DXA (68.6 ± 7.1 kg) and US (69.3 ± 6.0 kg) determined the lowest MWW, whereas those determined by SF (70.8 ± 6.8 kg) and ADP (70.9 ± 6.6 kg) were significantly greater (p< 0.05). The SEEs for MWW when compared with SF were 3.2, 3.4, and 2.4 kg for ADP, DXA, and US, respectively. Compared with SF, DXA and US would allow wrestlers to certify at a lower weight class 64 and 33% of the time, respectively. When comparing the approved methods (SF and ADP), approximately 50% of subjects would certify at a different weight class depending on the method used. The use of different methods in assessing %BF offer a wide variability in the determination of MWW.

Continuous moderate intensity versus discontinuous high intensity treadmill running on anterior cruciate ligament laxity and hamstrings flexibility in eumenorrheic women.

OBJECTIVE: To differentiate running intensity and menstrual phase effects on knee stability before and after exercise. METHODS: Ten eumenorrheic aerobically trained females were recruited to determine effects of a randomized crossover design of exercise intensity (85%HRR vs 42.5%HRR) on anterior cruciate ligament laxity (APLAX) and hamstrings flexibility (HF). A KT-2000 arthrometer measured APLAX and a 90-90 supine knee extension (MKE) and sit-and-reach test (SRD) measured HF in follicular (FP) and luteal (LP) menstrual cycle phases. RESULTS: Significant difference pre-exercise was observed for both 90N and 120N APLAX in LP compared to FP. Exercise increased APLAX at 90N and 120N in both FP and LP with LP exhibiting larger changes than FP. MKE and SRD increased significantly following exercise but were not different across menstrual phases or between exercise intensities. CONCLUSION: APLAX taken together with increased HF post-exercise demonstrates a less stable knee joint in the LP before and following exercise.

OBJECTIF: Distinguer les effets de l'intensité de la course sur tapis roulant et de ceux de la phase du cycle menstruel sur la stabilité du genou avant et après l'exercice. MÉTHODOLOGIE: On a recruté dix femmes ayant des règles normales, faisant de l'exercice aérobie, pour établir les effets d'un modèle croisé d'intensité de l'exercice physique (85 % HRR contre 42,5 % HRR) sur la laxité du ligament croisé antérieur (APLAX) et la souplesse des ischio-jambiers (SI). On a utilisé un arthromètre KT-2000 pour mesurer l'APLAX et l'extension en supination du genou à 90­90 (MKE) et on a utilisé le test de flexion du tronc pour mesurer la SI durant les phases folliculaire (PF) et lutéale (PL) du cycle menstruel. RÉSULTATS: On a observé une différence significative avant l'exercice physique pour 90° et 120° APLAX durant la PL par rapport à la PF. L'exercice physique a fait augmenter l'APLAX à 90° et à 120° autant dans la PF que dans la PL, les variations étant plus importantes dans la PL que dans la PF. MKE et SRD augmentaient de façon significative après l'exercice physique mais n'étaient pas différents durant les phases du cycle menstruel ou entre les intensités de l'exercice physique. CONCLUSION: L'APLAX en association avec la hausse de la SI post-exercice prouve une moins grande stabilité du genou durant la PL avant et après l'exercice physique.

The effect of music on anaerobic exercise performance and muscular endurance.

BACKGROUND: Music has been shown to improve aerobic and anaerobic exercise performance; however, music's effect on resistance training exercise, gender differences, and heart rate (HR) is less understood. The purpose of this study was to examine the effects of self-selected music on anaerobic exercise performance using a bench press (BP) protocol and the Wingate anaerobic test (WAT). METHODS: Fifteen (8 men; 7 women) healthy, college-aged students between 18-25 years old (20.1±1.79 yrs) participated in this study. Testing consisted of two trials (music [M]; no music [NM]] completed in a randomized order. Each participant performed the BP for a maximum number of repetitions using 70% one-repetition maximum for five sets. After a 10 min rest period, a 30 s Wingate anaerobic Test (WAT) was completed. RESULTS: During the M condition, there was a significant increase in total work (M: 16121.8±4287.3 kJ; NM: 15021.7±4370.6 kJ; P=0.024), relative peak power (M: 44.6±8.4 W; NM: 41.4±8.4 W; P=0.014), and the total number of bench press repetitions (M: 41.7±8.7 reps; NM: 38.3±8.1 reps; P=0.001). HR recovery following the WAT protocol was significantly quicker after the WAT protocol during the M condition (M: 256.2±54.5 sec.; NM 293.3±22.3 sec.; P=0.022). There was no significant condition as for gender interaction for any of the variables assessed. CONCLUSIONS: Listening to self-selected music improved exercise performance during the BP and the WAT. Music also hastened HR recovery following the WAT.

Salivary stress hormone response and performance in full competition after linear or undulating periodization training in elite powerlifters.

BACKGROUND: The purposes of this study were to determine differences in training loads and stress hormones among national level powerlifting competitors and the effect on performance. METHODS: Thirteen experienced male powerlifters provided detailed training logs during the 8 weeks prior to a national competition. Participants were divided into linear (LP, N.=6) and undulating periodization (UP, N.=7) training groups. Following weigh-ins and after successfully completing the competition, participants provided saliva samples. RESULTS: LP resulted in lower levels of salivary cortisol (sC) (LP 4.27±0.71 nmols/L; UP 5.53±0.78 nmols/L) and higher testosterone-to-cortisol ratio (T:C) (LP 8.03±0.84 nmols/L; UP 5.23±1.41 nmols/L) compared to UP prior to competition. Following competition, both LP and UP groups had significant increases in salivary testosterone (sT) (LP 383.70±34.96 nmols/L; UP 376.62±38.17 nmols/L) and sC (LP 17.67±1.39 nmols/L; UP 18.17±1.46 nmols/L) and significant reductions in T:C (LP 8.03±0.80 to 6.67±0.83; UP 5.23±1.41 to 4.95±1.00). Finally, the UP group had a significantly higher Wilks coefficient following the competition compared to the LP group (LP 440.7±31.83 vs. UP 480.29±24.13). CONCLUSIONS: It appears that the higher volume loads undertaken by UP have a larger perturbation on resting stress hormones; however, this does not seem to negatively influence powerlifting performance.

Differential Effects of Continuous Versus Discontinuous Aerobic Training on Blood Pressure and Hemodynamics.

Landram, MJ, Utter, AC, Baldari, C, Guidetti, L, McAnulty, SR, and Collier, SR. Differential effects of continuous versus discontinuous aerobic training on blood pressure and hemodynamics. J Strength Cond Res 32(1): 97-104, 2018-The purpose of this study was to compare the hemodynamic, arterial stiffness, and blood flow changes after 4 weeks of either continuous or discontinuous aerobic exercise in adults. Forty-seven subjects between the ages of 18 and 57 were recruited for 1 month of either continuous aerobic treadmill work for 30 minutes at 70% max heart rate or 3 bouts of 10 minutes of exercise at 70% of max heart rate with two 10 minutes break periods in between, totaling 30 minutes of aerobic work. After exercise, both continuous (CON) and discontinuous (DIS) groups demonstrated a significant improvement in maximal oxygen uptake (V[Combining Dot Above]O2max, CON 35.39 ± 1.99 to 38.19 ± 2.03; DIS 36.18 ± 1.82 to 39.33 ± 1.75), heart rate maximum (CON 183.5 ± 3.11 to 187.17 ± 3.06; DIS 179.06 ± 2.75 to 182 ± 2.61), decreases in systolic blood pressure (CON 119 ± 1.82 to 115.11 ± 1.50; DIS 117.44 ± 1.90 to 112.67 ± 1.66), diastolic blood pressure (CON 72.56 ± 1.65 to 70.56 ± 1.06; DIS 71.56 ± 1.59 to 69.56 ± 1.43), augmentation index (CON 17.17 ± 2.17 to 14.9 ± 1.92; DIS 19.71 ± 2.66 to 13.91 ± 2.46), central pulse wave velocity (CON 8.29 ± 0.32 to 6.92 ± 0.21; DIS 7.85 ± 0.30 to 6.83 ± 0.29), peripheral pulse wave velocity (CON 9.49 ± 0.35 to 7.72 ± 0.38; DIS 9.11 ± 0.37 to 7.58 ± 0.47), and significant increases in average forearm blood flow (CON 4.06 ± 0.12 to 4.34 ± 0.136; DIS 4.26 ± 0.18 to 4.53 ± 0.15), peak forearm blood flow (FBF) after reactive hyperemia (CON 28.45 ± 0.094 to 29.96 ± 0.45; DIS 29.29 ± 0.46 to 30.6 ± 0.38), area under the curve (AUC) of FBF (CON 28.65 ± 1.77 to 30.4 ± 1.08; DIS 30.52 ± 1.9 to 31.67 ± 1.44), and AUC peak FBF after reactive hyperemia (CON 222.3 ± 5.68 to 231.95 ± 4.42; DIS 230.81 ± 6.91 to 237.19 ± 5.39). These data suggest that for healthy people either 4 weeks of continuous or discontinuous aerobic training is effective in improving measures of fitness and vascular health.

Six weeks daily ingestion of whole blueberry powder increases natural killer cell counts and reduces arterial stiffness in sedentary males and females.

Evidence suggests that berries contain bioactive compounds, which reduce certain cancers and hypertension. Our hypothesis was that daily blueberry (BB) consumption would increase natural killer (NK) cells and plasma redox capacity and reduce blood pressure, augmentation index (AIx), central pulse wave velocity, and aortic systolic pressures (ASPs). Twenty-five men and postmenopausal women aged 18 to 50 years were recruited and randomized to BB (n, 13) or placebo groups (n, 12). Participants were provided with BB (equivalent to 250 g berries) or placebo powders each day for 6 weeks. Blood pressure, vascular performance testing, and blood samples were taken at baseline (presupplementation). Participants returned after 6 weeks and repeated all procedures. Presupplementation to postsupplementation comparisons for the main effects of treatment, time, and treatment-time interaction were made using a 2 (treatment) × 2 (times) repeated-measures analysis of variance for all vascular measures, redox status, and NK cell counts. Anthropometric measures were compared using t tests. Body mass, composition, and overall blood pressures were not affected in either group. Overall, AIx and ASPs were decreased in BB (treatment effect, P = .024 and P = .046, respectively). Plasma redox was not affected. Absolute NK cells were increased in BB (time, P = .001 and interaction, P = .012). Subjects (n, 9) with prehypertensive pressures (≥120/80 mm Hg, respectively) were examined as a subset using t tests and exhibited significant reductions in diastolic pressure (P = .038) from presupplementation to postsupplementation in BB. We conclude that BB ingestion for 6 weeks increases NK cells and reduces AIx, ASP, and diastolic pressures in sedentary males and females.

Treatment of prehypertension: lifestyle and/or medication.

Prehypertension is a warning to individuals with resting blood pressures between 120/80 mmHg and 139/89 mmHg of an insidious progression of blood pressure towards hypertensive levels (≥ 140/90 mmHg). Prehypertension is associated with increased cardiovascular risk and end organ damage compared with individuals who are normotensive. This review primarily focuses on internal and external factors associated with the prevalence of prehypertension. Elucidating all of the factors associated with a rise in resting blood pressure and comparing the effects of medication versus lifestyle changes may aid the clinician in developing a preventive and/or treatment strategy for each individual.

Evaluation of ultrasound velocity to assess the hydration status of wrestlers.

The objective of this study was to evaluate the utility of ultrasound velocity (UV) to detect changes in the hydration status of wrestlers after undergoing acute dehydration and a 2-hour rehydration period. Forty-seven NCAA wrestlers (mean+/-SEM); age 19.1+/-0.2 years, height 1.73+/-0.1 m, body mass (BM) 79.4+/-2.4 kg were tested in euhydrated, dehydrated, and a 2-hours rehydrated conditions. Hydration status was quantified by measuring changes in plasma osmolarity (Posm), urine osmolarity (Uosm), urine specific gravity (Usg), and BM. Ultrasound velocity was measured at 1 MHz using 1.5-microsecond duration tone burst in the soleus muscle. Significant changes (p<0.001) in UV during periods of dehydration (BM change=-3.6+/-0.14%) (UV=+2.18 m.s) and rehydration (BM change=+2.8+/-0.12%) (UV=-2.89 m.s) were found. Significant main effects (p<0.001) were also found for Usg, Uosm, and Posm during dehydration. The change in Posm from the 1 to 2-hour rehydration time period significantly correlated to the change in UV during the same time period (r=0.27, p<0.001). This study demonstrates that changes in UV correspond to the changes of Posm, Usg, Uosm, and BM during acute dehydration and rehydration in collegiate wrestlers. The use of ultrasound measures may have potential application as an alternative field-based method to assess the hydration status of collegiate wrestlers although future research is warranted.

Effect of n-3 fatty acids and antioxidants on oxidative stress after exercise.

PURPOSE: n-3 fatty acids are known to exert multiple beneficial effects including anti-inflammatory actions that may diminish oxidative stress. Supplementation with antioxidant vitamins has been proposed to counteract oxidative stress and improve antioxidant status. Therefore, this project investigated the effects of daily supplementation in 48 trained cyclists over 6 wk and during 3 d of continuous exercise on F2-isoprostanes (oxidative stress), plasma n-3 fatty acids, and antioxidant status (oxygen radical absorption capacity and ferric-reducing antioxidant potential). METHODS: Cyclists were randomized into n-3 fatty acids (N3) (n = 11) (2000 mg of eicosapentaenoic acid and 400 mg of docosahexaenoic acid), a vitamin-mineral (VM) complex (n = 12) emphasizing vitamins C (2000 mg), E (800 IU), A (3000 IU), and selenium (200 microg), a VM and n-3 fatty acid combination (VN3) (n = 13), or placebo (P) (n = 12). Blood was collected at baseline and preexercise and postexercise. A 4 x 3 repeated-measures ANOVA was performed to test main effects. RESULTS: After exercise, F2-isoprostanes were higher in N3 (treatment effect P = 0.014). Eicosapentaenoic acid and docosahexaenoic acid plasma values were higher after supplementation (interaction effect P = 0.001 and 0.006, respectively) in both n-3 supplemented groups. Oxygen radical absorption capacity declined similarly among all groups after exercise. Ferric-reducing antioxidant potential exhibited significant interaction (P = 0.045) and significantly increased after exercise in VN3 and VM (P < 0.01). CONCLUSIONS: This study indicates that supplementation with n-3 fatty acids alone significantly increases F2-isoprostanes after exhaustive exercise. Lastly, antioxidant supplementation augments plasma antioxidant status and modestly attenuates but does not prevent the significant n-3 fatty acid associated increase in F2-isoprostanes postexercise.

Quercetin supplementation does not alter antioxidant status in humans.

This study measured the influence of ingesting quercetin on plasma measures for oxidative stress and antioxidant capacity. Male and female subjects (n = 1002) varying in age (18-85 years) and body mass index (BMI) (16.7-52.7 kg/m(2)) were studied. Subjects were randomized to one of three groups using double-blinded methods: placebo, 500 mg or 1000 mg quercetin/day with 125 mg or 250 mg vitamin C/day, respectively. Pre- and post-study fasting blood samples show that plasma quercetin increased in a dose-responsive manner. The pattern of change in plasma F(2)-isoprostanes, oxidized low density lipoprotein, reduced glutathione, ferric reducing ability of plasma (FRAP) and oxygen radical absorbance capacity (ORAC) did not differ between supplementation groups or after adjustment for gender, age, BMI and disease status. In summary, quercetin supplementation over 12 weeks in doses of 500 mg or 1000 mg/day significantly increased plasma quercetin levels, but had no influence on several measures of oxidative stress and antioxidant capacity.