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1.
Front Sports Act Living ; 5: 1231371, 2023.
Article in English | MEDLINE | ID: mdl-37712007

ABSTRACT

Sport performance coaches use a range of modalities to apply a horizontal force (Fh) to athletes during resisted sprint training (RST). These modalities include parachutes, weighted vests, pulley devices, motored tethered devices, and, most notably, weighted sleds. Despite the widespread use of these devices, the resistance forces of the pulley devices have not been evaluated for reliability and accuracy. Therefore, the primary aim of this study is to quantify the Fh of a commercially available pulley device (EXER-GENIE®) and determine how resistance force is related to the load settings on the device. The secondary aim is to identify the differences in the Fh values between three EXER-GENIE® devices that use 36 m and 60 m ropes. The Fh values in the Newtons (N) of the three EXER-GENIE® devices were analyzed using a motorized winch, a lead acid battery, and an S-beam load cell. Four 10 s winch-driven trials were performed using 15 different EXER-GENIE® loads, ranging from 0.028 kg to 3.628 kg, employing two different 36 m devices and one 60 m device. The mean ± standard deviation for Fh was reported across the four trials for each load setting. All devices produced similar Fh values across lighter load settings (loads ≤0.141 kg). However, at heavier loads (loads ≥0.226 kg), the 60 m device had Fh values 50-85 N greater than those of the 36 m device. The coefficient of variation across the four trials was extremely high at light loads but sharply decreased to <10% at heavy loads. Absolute reliability was high for each device [intraclass correlation coefficient (ICC) = 0.99]. A regression analysis for Fh values and EXER-GENIE® load indicated a strong positive relationship between load and Fh values across all devices (R2 = 0.96-0.99). Caution should be exercised when using identical loads on the different-length pulley devices, as the 60 m device produced greater Fh values than the 36 m devices at load settings higher than 0.226 kg. These results can provide coaches and practitioners with a better understanding of the magnitude of resistance that is applied when prescribing EXER-GENIE® devices for higher training loads.

2.
J Funct Morphol Kinesiol ; 8(3)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37489301

ABSTRACT

L-citrulline serves as a nitric oxide precursor with the potential to increase blood flow and improve resistance exercise performance, yet more research is needed to examine its ergogenic potential. To examine the effect of L-citrulline supplementation on resistance exercise performance, muscle oxygenation, and the subjective perception of effort, energy, focus, fatigue, and muscle pump, eighteen resistance-trained men (n = 11) and women (n = 7) (21.4 ± 1.8 years; 172.3 ± 7.5 cm; 76.9 ± 10.8 kg) were randomly assigned for supplementation with 8 g of L-citrulline (CIT) or a placebo (PL) in a cross-over fashion one hour prior to testing. Participants completed an isometric mid-thigh pull test (IMTP), a ballistic bench press protocol [two sets of two repetitions at 75% 1-repetition maximum (1 RM) with maximum ballistic intent], and a strength-endurance bench press protocol [five repetition-maximum sets at 75% 1RM]. Barbell velocity and power were measured via a linear position transducer during the ballistic protocol, while the repetitions completed, volume load and muscle oxygenation were quantified during the strength-endurance protocol. Subjective measures were assessed at the baseline and immediately pre- and post-exercise. Repeated measures of the analysis of variance and Bayesian equivalents revealed no significant interactions, providing evidence favoring the null hypothesis (BF10 < 1) for IMTP (PL 497.5 ± 133.6 vs. CIT 492.5 ± 129.4 N), barbell velocity, and power, and repetitions completed (PL 36.7 ± 7.2 vs. CIT 36.9 ± 8.1 repetitions). There were also no significant interactions for muscle oxygenation parameters or subjective measures except perceived fatigue. Women reported greater fatigue across all time points compared to men (~1.88 au, p = 0.045, BF10 = 0.2). The results indicate that a single 8 g dose of L-citrulline did not enhance isometric force production, muscle endurance, or muscle oxygenation parameters during the protocol implemented in this study.

3.
Sports (Basel) ; 10(4)2022 Apr 08.
Article in English | MEDLINE | ID: mdl-35447867

ABSTRACT

This study examined the level of agreement (Pearson product-moment correlation [rP]), within- and between-day reliability (intraclass correlation coefficient [ICC]), and minimal detectable change of the MusclelabTM Laser Speed (MLS) device on sprint time and force−velocity−power profiles in Division II Collegiate athletes. Twenty-two athletes (soccer = 17, basketball = 2, volleyball = 3; 20.1 ± 1.5 y; 1.71 ± 0.11 m; 70.7 ± 12.5 kg) performed three 30-m (m) sprints on two separate occasions (seven days apart). Six time splits (5, 10, 15, 20, 25, and 30 m), horizontal force (HZT F0; N∙kg−1), peak velocity (VMAX; m∙s−1), horizontal power (HZT P0; W∙kg−1), and force−velocity slope (SFV; N·s·m−1·kg−1) were measured. Sprint data for the MLS were compared to the previously validated MySprint (MySp) app to assess for level of agreement. The MLS reported good to excellent reliability for within- and between-day trials (ICC = 0.69−0.98, ICC = 0.77−0.98, respectively). Despite a low level of agreement with HZT F0 (rP = 0.44), the MLS had moderate to excellent agreement across nine variables (rp = 0.68−0.98). Bland−Altman plots displayed significant proportional bias for VMAX (mean difference = 0.31 m∙s−1, MLS < MySp). Overall, the MLS is in agreement with the MySp app and is a reliable device for assessing sprint times, VMAX, HZT P0, and SFV. Proportional bias should be considered for VMAX when comparing the MLS to the MySp app.

4.
Eur J Appl Physiol ; 122(7): 1627-1638, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35429293

ABSTRACT

INTRODUCTION: Watermelon shows promise as an ergogenic aid due to its high concentration of L-citrulline, vitamins, minerals, and antioxidants. PURPOSE: The purpose of this study was to examine the effect of watermelon supplementation on exercise performance, muscle oxygenation, and vessel diameter. METHODS: In a crossover design fashion, 15 resistance-trained men (22.4 ± 2.9 years; 177.5 ± 7.1 cm; 82.7 ± 11.2 kg) were randomly assigned to supplement with either watermelon juice concentrate (WM; 2.2 g·day-1 L-citrulline) or placebo (PL) for 7 days prior to completing an experimental trial consisting of an isometric mid-thigh pull test and acute bench press protocol. Participants completed two sets of two repetitions at 75% 1 repetition maximum (1-RM) with maximum ballistic intent followed by five repetition-maximum (RM) sets at the same load. Barbell velocity and power were measured via linear position transducer during the first two sets, while volume load and muscle oxygenation were quantified during RM sets. Brachial artery diameter and subjective perception measures were assessed at baseline and immediately pre- and post-exercise. RESULTS: Except for a greater percent change in skeletal muscle oxygenation during WM compared to PL on average and across sets (mean difference = + 4.1%, p = 0.033, BF10 = 2.2-54.5), separate traditional and Bayesian analyses of variance with repeated measures, as well as paired-samples t tests for calculated summary measures, revealed no evidence favoring conditional differences in any measure of performance, perception, or muscle oxygenation. CONCLUSION: Short-term watermelon supplementation does not appear to enhance isometric force production, bench press performance, blood vessel diameter, or muscle oxygenation parameters compared to PL in resistance-trained men.


Subject(s)
Citrullus , Resistance Training , Bayes Theorem , Citrulline , Dietary Supplements , Double-Blind Method , Humans , Male , Muscle Strength , Muscle, Skeletal/physiology
5.
J Strength Cond Res ; 35(10): 2915-2917, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34550099

ABSTRACT

ABSTRACT: Sell, KM, Ghigiarelli, JJ, Prendergast, JM, Ciani, GJ, Martin, J, and Gonzalez, AM. Comparison of V̇o2peak and V̇o2max at different sampling intervals in collegiate wrestlers. J Strength Cond Res 35(10): 2915-2917, 2021-The purpose of this study was to determine the difference in the highest oxygen uptake (V̇o2peak) achieved during a maximal effort graded exercise test (GXT) in 20 NCAA Division I male wrestlers using breath-by-breath (BbB) values to the maximal uptake averaged across different time- and breath-based oxygen consumption sampling intervals (V̇o2max). Given the need for aerobic fitness and anaerobic power in wrestling, the accurate determination of V̇o2max is imperative if it is to be used to identify current aerobic fitness and consequently guide sport-specific training programs to address weaknesses in this area. Each subject completed a cycle ergometer GXT during which BbB data were collected via indirect calorimetry and V̇o2peak determined as the highest value. V̇o2max was considered as the average value of 3-s, 5-s, 10-s, 20-s, and 30-s sampling, and 3-b, 7-b, and 11-b sampling during the GXT. Results show that the BbB V̇o2peak was significantly higher than the 5-s, 10-s, 20-s, 30-s, and 11-b (p < 0.05). The 3-b V̇o2max was significantly higher than the 20-s and 30-s V̇o2max values (p < 0.05). The underestimation of V̇o2peak for each time-based interval sampling approach compared with BbB V̇o2peak is consistent with previous research, but the comparison of BbB data to breath-based interval sampling has not been widely addressed in prior research. The use of a 7-b sampling interval for the determination of V̇o2max may be a promising approach to minimize the systematic errors associated with BbB or less frequent sampling intervals, but future research is needed to further support its application with elite athletic populations such as those in the current study.


Subject(s)
Oxygen Consumption , Wrestling , Athletes , Exercise , Exercise Test , Humans , Male
7.
Article in English | MEDLINE | ID: mdl-33345040

ABSTRACT

Photobiomodulation therapy (PBMT) can be applied to the whole body as compared to the application of using single hand-held devices that isolate a smaller muscle area. The purpose of this study was to examine the effects of an acute dose of whole-body PBMT pre- and post-high-intensity resistance training on creatine kinase (CK) and salivary interleukin-6 (IL-6) in a sample of trained males. Twelve males (31 ± 8.3 years, 177.2 ± 5.4 cm, and 86.0 ± 7.5 kg) were part of a randomized, counterbalanced, cross-over design, whereby each participant performed a high-intensity resistance training session that consisted of the bench press, chin-up, and repeated sprints on two separate occasions. Each participant was assigned to either the PBMT or control condition on two separate weeks, with a 10-days washout period between the weeks. Creatine kinase was measured at baseline, 24, 48, and 72 h post-exercise. Salivary IL-6 was measured at baseline, 60, 90, and 120 min. A paired t-test showed no significant difference (p = 0.669) in the area under the curve (AUC) for CK during the PBMT (191.7 ± 48.3) and control conditions (200.2 ± 68.0). A Wilcoxon signed-rank test also showed no significant median difference (p = 0.155) in the AUC for salivary IL-6 during the PBMT (Mdn = 347.7) and control conditions (Mdn = 305.8). An additional Wilcoxon signed-rank test for CK percentage change from 24 to 72 h showed the PBMT condition (Mdn = -45%) to have a -18% median difference as compared to the control condition (Mdn = -41%). As such, whole-body PBMT does not significantly reduce the activity of salivary IL-6 or CK concentration during the 24 to 72-h recovery post-high-intensity resistance training.

8.
Sports (Basel) ; 7(5)2019 May 23.
Article in English | MEDLINE | ID: mdl-31126039

ABSTRACT

To determine the agreement between the Open Barbell (OB) and Tendo weightlifting analyzer (TWA) for measuring barbell velocity, eleven men (19.4 ± 1.0 y) performed one set of 2-3 repetitions at four sub-maximal percentage loads, [i.e., 30, 50, 70, and 90% one-repetition maximum (1RM)] in the back (BS) and front squat (FS) exercises. During each repetition, peak and mean barbell velocity were recorded by OB and TWA devices, and the average of the 2-3 repetitions was used for analyses. Although the repeated measures analysis of variance revealed significantly (p ≤ 0.005) greater peak and mean velocity scores from OB across all intensities, high intraclass correlation coefficients (ICC2,K = 0.790-0.998), low standard error of measurement (SEM2,K = 0.040-0.119 m·s-1), and coefficients of variation (CV = 2-4%) suggested consistency between devices. Positive (r = 0.491-0.949) Pearson correlations between averages and differences (between devices) in peak velocity, as well as associated Bland-Altman plots, showed greater differences occurred as the velocity increased, particularly at low-moderate intensity loads. OB consistently provides greater barbell velocity scores compared to TWA, and the differences between devices were more apparent as the peak velocity increased with low-to-moderate loads. Strength coaches and athletes may find better agreement between devices if the mean velocity scores are only considered.

9.
J Strength Cond Res ; 33(2): 301-306, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30688871

ABSTRACT

Spitz, RW, Gonzalez, AM, Ghigiarelli, JJ, Sell, KM, and Mangine, GT. Load-velocity relationships of the back vs. front squat exercises in resistance-trained men. J Strength Cond Res 33(2): 301-306, 2019-The purpose of this investigation was to describe and compare changes in barbell velocity in relation to relative load increases during the back squat (BS) and front squat (FS) exercises. Eleven National Collegiate Athletic Association Division I baseball position players (19.4 ± 1.0 years; 182.4 ± 6.5 cm; and 87.2 ± 7.4 kg) performed trials at maximum speed with loads of 30, 50, 70, and 90% of their predetermined 1 repetition maximum (1RM) for both BS and FS. Peak and mean velocity was recorded during each repetition using an accelerometer. Differences between exercises and relative loading were assessed by separate 2 × 4 (condition × relative load) repeated-measures analysis of variance for mean and peak velocity. In addition, the load-velocity relationship across submaximal loadings in BS and FS were further assessed by calculating their respective slopes and comparing slopes through a paired-samples t-test. No significant condition × relative load interactions were noted for mean velocity (p = 0.072) or peak velocity (p = 0.203). Likewise, no significant differences in the slope for BS and FS were noted for mean velocity (p = 0.057) or peak velocity (p = 0.196). However, significant main effects for relative load were noted for both mean and peak velocity (p < 0.001), whereby mean and peak velocity were progressively reduced across all relative loads (i.e., 30, 50, 70, and 90% 1RM) for both the BS and FS. Our results demonstrate that the load-velocity relationships of the BS and FS exercises seem to be similar; therefore, similar approaches may be used with these squat variations when monitoring barbell velocity or implementing velocity-based strength training.


Subject(s)
Baseball/physiology , Muscle Strength/physiology , Muscle, Skeletal/physiology , Resistance Training/methods , Weight Lifting/physiology , Athletes , Cross-Over Studies , Exercise Test , Humans , Male , Posture , Young Adult
10.
J Strength Cond Res ; 32(11): 3160-3168, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30216251

ABSTRACT

Sell, KM, Prendergast, JM, Ghigiarelli, JJ, Gonzalez, AM, Biscardi, LM, Jajtner, AR, and Rothstein, AS. Comparison of physical fitness parameters for starters vs. nonstarters in an NCAA Division I men's lacrosse team. J Strength Cond Res 32(11): 3160-3168, 2018-The purpose of this study was to present a fitness profile of Division I male lacrosse players and compare the fitness attributes across different positions and starting status. Forty-one Division I men's lacrosse players (19.6 ± 1.6 years, 82.5 ± 9.5 kg, 182.0 ± 5.4 cm) volunteered to participate in the study. Fitness attributes assessed included aerobic fitness (1.5-mile run), muscular strength (1 repetition maximum bench press, squat, and hang clean), grip strength (hand dynamometer), explosive power (vertical jump), agility (3-cone drill, pro-agility), body composition (7-site skinfold), and speed (20- and 40-yard sprint). All testing was conducted by a certified strength and conditioning coach and occurred at the conclusion of pre-season training. The only significant difference across positions was for body mass, whereby defensemen were significantly heavier than attacking players (p < 0.05). Starters were significantly faster on the 3-cone drill, 20- and 40-yard sprint, and jumped significantly higher on the vertical jump compared with nonstarters (p < 0.05). Attributes pertaining to anaerobic fitness (speed, agility, and explosive power) may be better predictors of starting status than aerobic fitness in men's NCAA Division I lacrosse players. This differs from previous research on men's club lacrosse players where a difference in aerobic fitness and body composition was shown between starters and nonstarters. The normative data presented in this study may assist strength and conditioning coaches in the development of sport-specific training programs and motivate athletes toward achieving sport-specific fitness goals by helping identify areas of weakness before the start of the season.


Subject(s)
Athletic Performance , Physical Fitness , Racquet Sports , Athletes , Body Composition , Exercise Test , Humans , Male , Muscle Strength , Young Adult
11.
J Strength Cond Res ; 32(4): 938-949, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29309385

ABSTRACT

Ghigiarelli, JJ, Pelton, LM, Gonzalez, AM, Fulop, AM, Gee, JY, and Sell, KM. Effects of a 6-week bench press program using the freak bar in a sample of collegiate club powerlifters. J Strength Cond Res 32(4): 938-949, 2018-Powerlifters train using specialty bars for unstable load (UL) training. For the bench press, the acute effects of UL are mixed, with few studies that examine training interventions. The purpose of this study was to examine the effects of a 6-week bench press training program that uses the Freak Bar (FB) as compared to a traditional barbell (TB) on maximum bench press, peak force, and peak impulse. Seven men and 3 women (21 ± 2.0 years, 172.2 ± 2.9 cm, and 95.3 ± 20.3 kg) were required to bench press 2 days per week as part of a structured program. On the second bench press day, the FB and TB groups performed 3-position pause bench presses at 60-70% one repetition maximum (1RM). One repetition maximum, peak force, and peak impulse were measured before test and after test after the 6-week program. Peak force and peak impulse were tested at 3 bench positions, including the presticking, sticking, and poststicking points, defined by the distance of the barbell from the chest. Posttraining 1RM for the FB group and TB group increased 6.7% (6.78 ± 1.6 kg, p = 0.006) and 4.3% (4.5 ± 2.7 kg, p = 0.23), respectively, with no significant differences between the groups (p = 0.589, ηp = 0.044). There were no significant differences between the groups at each bench position for peak force (p = 0.606) or peak impulse (p = 0.542). Freak Bar can be an alternative for improving maximum strength and peak force but is not significantly better than TB training when performing the 3-position pause bench press.


Subject(s)
Muscle Strength/physiology , Muscle, Skeletal/physiology , Resistance Training/methods , Weight Lifting/physiology , Female , Humans , Male , Universities , Young Adult
12.
J Diet Suppl ; 15(6): 965-976, 2018 Nov 02.
Article in English | MEDLINE | ID: mdl-29336628

ABSTRACT

The purpose of this investigation was to examine the effects of 28 days of a dietary supplement on body composition, mood, and satiety in overweight adults. Twenty healthy adults (25.5 ± 3.8 years; 87.3 ± 20.7 kg; 169.9 ± 10.6 cm; 29.9 ± 5.1 body mass index) participated in this randomized, double-blind, placebo-controlled investigation. Ten participants were provided with a dietary supplement containing 178 mg satiereal, 100 mg naringin, and 2,000 IU vitamin D3 daily (SUPP), and ten participants were provided a placebo (PL) for 28 days. Baseline (PRE) and post (POST) assessments included body mass, BMI, and waist circumference measures. In addition, participants provided self-reported food records and completed study questionnaires twice weekly. Questionnaires consisted of profile of mood states, visual analog scales, modified trait food-cravings questionnaire, and a modified state food-cravings questionnaire. No significant differences were noted between groups for total calorie or macronutrient intake (p = 0.65-0.92), body mass (p = 0.34), BMI (p = 0.24), or waist circumference measures (p = 0.56-0.94). In addition, no significant differences between groups were observed for mood states, subjective measures of food cravings, or feelings of anxiety, fullness, bloating, hunger, craving, and stress (p >.05). In conclusion, 28 days of a dietary supplement containing satiereal, naringin, and vitamin D3 did not have any detectable beneficial effects on body-weight management.


Subject(s)
Affect/drug effects , Body Composition/drug effects , Cholecalciferol/administration & dosage , Flavanones/administration & dosage , Overweight/drug therapy , Adult , Body Mass Index , Cholecalciferol/analysis , Dietary Supplements/analysis , Double-Blind Method , Energy Intake , Exercise , Flavanones/analysis , Humans , Overweight/physiopathology , Overweight/psychology , Placebos , Satiation/drug effects , Surveys and Questionnaires , Waist Circumference
13.
J Strength Cond Res ; 32(11): 3088-3094, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29210953

ABSTRACT

Gonzalez, AM, Spitz, RW, Ghigiarelli, JJ, Sell, KM, and Mangine, GT. Acute effect of citrulline malate supplementation on upper-body resistance exercise performance in recreationally resistance-trained men. J Strength Cond Res 32(11): 3088-3094, 2018-To investigate the effect of citrulline malate (CM) supplementation on upper-body resistance exercise performance, 12 recreationally resistance-trained men (21.4 ± 1.6 years; 163.0 ± 46.2 cm; 85.0 ± 12.4 kg) underwent 2 testing sessions administered in a randomized, double-blind fashion. During each visit, participants were provided either 8 g of CM or a placebo (PL) 40 minutes before beginning a standardized warm-up and initiating a barbell bench press resistance exercise protocol consisting of 5 sets of 15 repetitions at 75% 1 repetition maximum with 2-minute rest intervals. Participants were instructed to complete as many repetitions as possible until either reaching 15 repetitions or muscular failure. Total number of repetitions performed and power output were recorded for each set. Subjective measures of energy, focus, fatigue, and perceived exertion, along with muscle thickness of the triceps brachii, were assessed before and after exercise. Significant (p ≤ 0.05) main effects for time were observed for all variables except for subjective feelings of energy (p = 0.085). A group × time interaction (F = 2.86, p = 0.034, n = 0.21) was observed for repetitions performed, where participants performed more (p = 0.015) repetitions on set 3 during PL (5.7 ± 1.2 repetitions) compared with CM (4.6 ± 1.2 repetitions). However, during set 4, participants tended (p = 0.089) to perform more repetitions during CM (4.8 ± 1.8 repetitions) compared with PL (4.3 ± 1.3 repetitions). No other differences were observed between trials. Supplementation with 8 g of CM 40 minutes before the barbell bench press resistance exercise protocol did not increase exercise performance, augment the muscle swelling response to training, or alter subjective measures of focus, energy, and fatigue in recreationally resistance-trained men.


Subject(s)
Athletic Performance/physiology , Citrulline/analogs & derivatives , Dietary Supplements , Malates/pharmacology , Resistance Training , Weight Lifting/physiology , Citrulline/pharmacology , Cross-Over Studies , Double-Blind Method , Fatigue , Humans , Male , Muscle, Skeletal/physiology , Rest , Young Adult
14.
Appl Physiol Nutr Metab ; 42(4): 443-448, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28177725

ABSTRACT

The purpose of this study was to investigate the effects of phosphatidic acid (PA) supplementation on muscle thickness and strength following an 8 week supervised resistance-training program. Fifteen resistance trained men (22.8 ± 3.5 years; 80.6 ± 8.7 kg; 178.1 ± 5.6 cm; 14.6% ± 8.8% body fat) were randomly assigned to a group that either consumed 750 mg of PA or a placebo (PL). Testing was carried out before (PRE) and after (POST) training/supplementation for muscle thickness and strength. Muscle thickness of the rectus femoris (RF), vastus lateralis (VL), biceps brachii (BB), and triceps brachii (TB) muscles were measured via ultrasonography, along with 1 repetition maximum (1RM) of squat, deadlift, and bench press. Analysis of covariance (ANCOVA), using PRE values as the covariate, did not reveal any group differences for measures of muscle thickness in the RF (PA: 3.6% ± 5.2%; PL: 3.2% ± 4.2%, p = 0.97), VL (PA: 23.4% ± 18.1%, PL: 12.5% ± 15.4%, p = 0.37), BB (PA: 3.7% ± 6.4%, PL: 9.6% ± 12.4%, p = 0.86), or TB (PA: 15.1% ± 17.9%, PL: 10.7% ± 19.3%, p = 0.79). Likewise, no group differences were observed in changes in squat (PA: 8.4% ± 4.1%, PL: 8.1% ± 4.2%, p = 0.79), deadlift (PA: 10.1% ± 10.1%, PL: 8.9% ± 9.5%, p = 0.66), or bench press (PA: 5.7% ± 5.5%, PL: 5.1% ± 3.0%, p = 0.76) exercises. Collectively, however, all participants experienced significant (p < 0.05) improvements in each measure of muscle thickness and strength. Results of this study suggest that PA supplementation, in combination with a 3 days·week-1 resistance-training program for 8 weeks, did not have a differential effect compared with PL on changes in muscle thickness or 1RM strength.


Subject(s)
Athletic Performance , Dietary Supplements , Muscle Development , Muscle Strength , Performance-Enhancing Substances/administration & dosage , Phosphatidic Acids/administration & dosage , Resistance Training , Adult , Athletes , Dietary Fats/administration & dosage , Dietary Fats/adverse effects , Dietary Supplements/adverse effects , Double-Blind Method , Humans , Male , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/growth & development , Patient Compliance , Performance-Enhancing Substances/adverse effects , Phosphatidic Acids/adverse effects , Reproducibility of Results , Ultrasonography , Weight Lifting , Young Adult
15.
Muscle Nerve ; 56(3): 505-509, 2017 09.
Article in English | MEDLINE | ID: mdl-27935085

ABSTRACT

INTRODUCTION: Muscle activation was investigated during resistance exercise with 2 relatively high-intensity loads. METHODS: Ten resistance-trained men performed the leg press exercise to repetition failure: a set at 70% of 1-repetition maximum (1RM) and a set at 90% of 1RM. Surface electromyography (EMG) was used to assess peak and mean muscle activation of the vastus lateralis, rectus femoris, and vastus medialis. RESULTS: Peak and mean EMG remained greater at 90% than 70% 1RM across all repetitions (P = 0.03 and P = 0.02, respectively). Main effects for trial were also significant for mean EMG activity of the final common repetitions (P = 0.03) favoring 90% 1RM; however, peak EMG activity was similar during the final common repetitions of the 70% and 90% 1RM sets. CONCLUSIONS: Across all repetitions, 90% 1RM appears to produce greater muscle activation during the leg press exercise, but similar peak EMG was observed during the final common repetitions of each set. Muscle Nerve 56: 505-509, 2017.


Subject(s)
Electromyography/methods , Exercise/physiology , Muscle Strength/physiology , Quadriceps Muscle/physiology , Resistance Training/methods , Weight-Bearing/physiology , Adult , Humans , Male , Young Adult
16.
J Strength Cond Res ; 27(3): 738-47, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23443220

ABSTRACT

Strongman exercises consist of multi-joint movements that incorporate large muscle mass groups and impose a substantial amount of neuromuscular stress. The purpose of this study was to examine salivary testosterone responses from 2 novel strongman training (ST) protocols in comparison with an established hypertrophic (H) protocol reported to acutely elevate testosterone levels. Sixteen men (24 ± 4.4 years, 181.2 ± 6.8 cm, and 95.3 ± 20.3 kg) volunteered to participate in this study. Subjects completed 3 protocols designed to ensure equal total volume (sets and repetitions), rest period, and intensity between the groups. Exercise sets were performed to failure. Exercise selection and intensity (3 sets × 10 repetitions at 75% 1 repetition maximum) were chosen as they reflected commonly prescribed resistance exercise protocols recognized to elicit a large acute hormonal response. In each of the protocols, subjects were required to perform 3 sets to muscle failure of 5 different exercises (tire flip, chain drag, farmers walk, keg carry, and atlas stone lift) with a 2-minute rest interval between sets and a 3-minute rest interval between exercises. Saliva samples were collected pre-exercise (PRE), immediate postexercise (PST), and 30 minutes postexercise (30PST). Delta scores indicated a significant difference between PRE and PST testosterone level within each group (p ≤ 0.05), with no significant difference between the groups. Testosterone levels spiked 136% (225.23 ± 148.01 pg·ml(-1)) for the H group, 74% (132.04 ± 98.09 pg·ml(-1)) for the ST group, and 54% (122.10 ± 140.67 pg·ml) for the mixed strongman/hypertrophy (XST) group. A significant difference for testosterone level occurred over time (PST to 30PST) for the H group p ≤ 0.05. In conclusion, ST elicits an acute endocrine response similar to a recognized H protocol when equated for duration and exercise intensity.


Subject(s)
Physical Education and Training/methods , Saliva/chemistry , Testosterone/analysis , Weight Lifting/physiology , Adolescent , Adult , Analysis of Variance , Humans , Male , Young Adult
17.
J Strength Cond Res ; 25(5): 1193-203, 2011 May.
Article in English | MEDLINE | ID: mdl-21478765

ABSTRACT

Several studies have documented the normative data for football combine performance measures in college and professional players. The primary purpose of this study was to examine the anthropometric and combine performance differences between highly recruited and recruited high school football players. A secondary purpose was to provide a historical basis of descriptive data for elite high school football players from 2001 to 2009. Height, weight, 40-yd sprint time, 20-yd shuttle time, vertical jump height, angle drive drill time, and broad jump distance were extracted for 2,560 players from a commercially available website. Mean scores across star value and playing positions were compared using analysis of variance (ANOVA) and 1-way ANOVAs. Statistical significance was found between highly recruited (5 and 4 stars) and recruited players (3 and 2 stars) for height (highly recruited = 1.878 ± 0.06 m, recruited 1.85 ± 0.11 m), weight (highly recruited = 99.77 ± 4.76 kg, recruited = 97.54 ± 4.84 kg), 40-yd sprint (highly recruited = 4.76 ± 0.327 seconds, recruited = 4.84 ± 0.142 seconds), and vertical jump (highly recruited = 0.775 ± 0.11 m, recruited = 0.750 ± 0.121 m). Ten backward stepwise regression models were calculated (position × variables) with statistical significance set at the p < 0.05 level. The 40-yd sprint time, height, and weight were significant predictors of star value across 10 positions. These data provide anthropometric and performance profiles for highly recruited high school football players. Sprinting ability and physical size are the most consistent predictors of subjective ranking. The results may help strength and conditioning specialists better understand the anthropometric and physical attributes that distinguish highly recruited from recruited players and which attributes are likely to predict higher star value scores.


Subject(s)
Athletic Performance/physiology , Exercise Test/methods , Football/physiology , Personnel Selection/methods , Adolescent , Analysis of Variance , Anthropometry , Cross-Sectional Studies , Humans , Male , Physical Fitness/physiology , Predictive Value of Tests , Regression Analysis , Retrospective Studies , Young Adult
18.
J Strength Cond Res ; 23(3): 756-64, 2009 May.
Article in English | MEDLINE | ID: mdl-19387404

ABSTRACT

The purpose of this study was to explore the effects of a 7-week heavy elastic band and weighted-chain program on maximum muscular strength and maximum power in the bench press exercise. Thirty-six (n = 36) healthy men aged 18-30 years old, from the Robert Morris University football team, volunteered to participate in this study. During the first week, predicted 1 repetition maximum (1RM) bench press and a 5RM speed bench press tests were conducted. Subjects were randomly divided into 3 groups (n = 12): elastic band (EB), weighted chain (WC), and traditional bench (C). During weeks 2-8 of the study, subjects were required to follow the prescribed resistance training program. Mean and SD of the predicted 1RM bench press and 5RM speed bench press were computed. A two-factor (method X time) analysis was applied to identify significant differences between the training groups. Significance was set at alpha = 0.05. Results indicated a significant time (p < 0.05) but no group effect for both predicted 1RM (kg) and 5RM peak power tests (watts). Although not significant, results did show greater nonsignificant improvements in the EB (848-883 W) and WC groups (856-878 W) vs. control (918-928 W) when the 2 highest and greatest values were selected regarding peak power. The use of EB and WC in conjunction with a general off-season strength and conditioning program can increase overall maximum upper-body strength in a sample of Division 1-AA football players. These types of training modalities add a unique training style and more flexibility with respect to exercise prescription for athletes and strength practitioners.


Subject(s)
Football/physiology , Muscle Strength/physiology , Muscle, Skeletal/physiology , Physical Education and Training/methods , Thorax/physiology , Adolescent , Adult , Analysis of Variance , Factor Analysis, Statistical , Humans , Male
19.
Med Sci Sports Exerc ; 38(1): 158-66, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16394969

ABSTRACT

PURPOSE: Concurrent and construct validity of a kinematic exertional observation procedure was examined for 10- to 14-yr-old female (N = 22) and male (N = 22) healthy children. METHODS: A load-incremented treadmill test protocol employing speed/grade changes every 3 min was used. RPE for the overall body (RPE-Overall), legs (RPE-Legs), and chest (RPE-Chest) were simultaneously estimated by an independent observer and self-rated by a subject during each treadmill stage using the Children's OMNI-Walk/Run Scale. Subjects' HR and oxygen consumption (VO2) were measured during each stage. Concurrent validity was established by correlating the observer's RPE with the subject's HR and VO2. Construct validity was examined by correlating submaximal RPE estimated by the observer with RPE estimated by the subject. RESULTS: The range of responses for the females and males was VO2 = 18.4-43.5 mL x kg(-1) x min(-1), HR = 121-185 bpm, and OMNI Scale RPE- (Overall, -Legs, -Chest) ranging from 1 to 9. Observer RPE (Overall, -Legs, -Chest) for the female and male subjects ranged from 1 to 9. For both female and male groups regression analyses indicated that observer's RPE distributed as a positive function of subject's HR and VO2; r = 0.80-0.91 (P < 0.01). Observer's RPE distributed as a positive function of subject's RPE for both females and males; r = 0.87-0.92 (P < 0.01). CONCLUSION: Results support the validity of a direct kinematic observation procedure to estimate OMNI Scale RPE for female and male children performing treadmill exercise. Exertional observation provides an unobtrusive perceptual estimate of exercise intensity and could be included in standardized physical activity assessments for children.


Subject(s)
Exercise Test/methods , Observation , Physical Exertion/physiology , Adolescent , Child , Cross-Sectional Studies , Female , Humans , Male , Pennsylvania
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