Heavy Resistance Exercise Protocol Research Articles

Ballistic Exercise Versus Heavy Resistance Exercise Protocols: Which Resistance Priming Is More Effective for Improving Neuromuscular Performance on the Following Day?

Nishioka, T and Okada, J. Ballistic exercise versus heavy resistance exercise protocols: which resistance priming is more effective for improving neuromuscular performance on the following day? J Strength Cond Res XX(X): 000-000, 2023-This study aimed to determine whether ballistic exercise priming (BEP) or heavy resistance priming (HRP) is more effective for improving ballistic performance after 24 hours. Ten resistance-trained men performed BEP and HRP conditions 72-144 hours apart in a randomized and counterbalanced order. Jumping performance was assessed before and 24 hours after the BEP and HRP sessions using 0 and 40% one-repetition maximum (1RM) squat jump (SJ), 0 and 40% 1RM countermovement jump (CMJ), and drop jump (DJ) reactive strength index (RSI). Statistical significance was accepted at p ≤ 0.05. In the BEP condition, 0% 1RM CMJ height (+3.62%) as well as theoretical maximum velocity (+5.14%) and theoretical maximum power (+2.55%) obtained from CMJ 24 hours after the priming session were significantly greater than those at the baseline (p ≤ 0.05), but 0% 1RM SJ height and DJ RSI (p > 0.05) were not greater than those at the baseline. In the HRP condition, the jump performances were not improved (p > 0.05). The percentage change in 0% 1RM CMJ height in the BEP condition was significantly greater than that seen in the HRP condition (p = 0.015) but did not differ for 0% 1RM SJ height and DJ RSI (p > 0.05). These results suggest that the BEP is more effective than HRP in improving CMJ performance after 24 hours. Therefore, practitioners should consider prescribing resistance priming using low-load ballistic exercises rather than high-load traditional exercises when planning to enhance athlete performance on the following day.

Acute effects of ballistic versus heavy-resistance exercises on countermovement jump and rear-hand straight punch performance in amateur boxers

BackgroundBallistic and heavy-resistance exercises may potentially enhance lower body power, which is paramount for the punching performance of amateur boxers. This study aimed to determine the acute effects of ballistic exercise (BE) and heavy-resistance exercise (HRE) on countermovement jump (CMJ) and rear-hand straight punch performance in amateur boxers.MethodsTen amateur boxers performed two conditioning exercises in a randomized and counterbalanced order as follows: squat jump with 4 sets × 8 repetitions at 30% one-repetition maximum (1RM) for BE and squat with 3 sets × 5 repetitions at 80% 1RM for HRE. The jump height (JH), relative maximal force (RMF), relative maximal power (RMP) of the CMJ, punch force (PF), and punch speed (PS) of a rear-hand straight punch were measured before and 3, 6, 9, and 12 min after either BE or HRE.ResultsNo significant condition × time interaction was found for JH (p = 0.303), RMF (p = 0.875), RMP (p = 0.480), PF (p = 0.939), and PS (p = 0.939). In addition, no main effect of the condition for JH (p = 0.924), RMF (p = 0.750), RMP (p = 0.631), PF (p = 0.678), and PS (p = 0.712). A significant main effect of time was observed for PF (p = 0.001) and PS (p = 0.001), whereas JH (p = 0.081), RMF (p = 0.141), and RMP (p = 0.430) were not. Pairwise comparison identified that PF (p = 0.031) and PS (p = 0.005) significantly increased at 9 min compared with those at baseline.ConclusionsThe findings of this study demonstrated that BE and HRE protocols can potentiate the rear-hand straight punch performance at 9 min but bring less favorable improvements for JH, RMF, or RMP of CMJ.

Acute Effects of Resistance Exercise and the Use of GH or IGF-1 Hormones on Oxidative Stress and Antioxidant Markers in Bodybuilders.

The aim of this study was to examine the influence of peptide hormone use on oxidative stress and antioxidant responses to a single session of resistance exercise in male bodybuilders. Forty-five male bodybuilders were divided into three groups: bodybuilders using growth hormone for at least 1 year (i.e., 3 to 4 times in the year) (GH-user, n = 15), bodybuilders using insulin-like growth factor-1 for at least 1 year (i.e., 3 to 4 times in the year) (IGF-1-user, n = 15), and peptide hormone-free bodybuilders (Non-user, n = 15). The heavy resistance exercise protocol consisted of five sets with 80% of one repetition maximum for six exercises. Blood samples were obtained pre and post heavy resistance exercise (HRE) in order to evaluate changes in oxidative stress (8-hydroxy-2-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and nitric oxide (NO)) and antioxidant biomarkers (glutathione peroxidase (GPx), catalase (CAT) and glutamate (GLU)) level. All the experimental groups showed increases in MDA (p = 0.038), NO (p = 0.028), GPx (p = 0.012), and GLU (p = 0.003) concentrations after resistance exercise. For 8-OHdG, the Non-user and IGF-1-user groups indicated increases at post-exercise (p = 0.001), without any significant changes in the GH-user group (p = 0.87). In addition, the changes in serum GPx and GLU levels were greater for the GH-user group than the Non-user and IGF-1-user groups (p = 0.001). In conclusion, HRE induced significant increases in 8-OHdG (except to GH-user group), MDA, NO, GPx, and GLU levels with greater changes in GPx and GLU for the GH-user group.

Acute Heavy Resistance Exercise Protocol Induces Significant Physiological Stress Elevating Extracellular Heat Shock Protein

Acute Heavy Resistance Exercise Protocol Induces Significant Physiological Stress Elevating Extracellular Heat Shock Protein

Physiological Effects of Nucleotide Supplementation on Resistance Exercise Stress in Men and Women

Nucleotide supplementation can reduce postexercise immunosuppression and hypothalamic-pituitary axis (HPA) axis activation in endurance exercise models. Nucleotide supplementation may aid recovery from other exercise modalities, such as heavy resistance exercise. Thus, the purpose of this investigation was to investigate the effects of nucleotide supplementation on the acute cortisol and immune responses to heavy resistance exercise and its effects on recovery. A double-blinded, crossover, mixed methods design with 10 men and 10 women was used. Each performed an acute heavy resistance exercise protocol (AHREP) after a loading period with a nucleotide or placebo supplement. Before and after the AHREP, and at 24, 48, and 72 hours post, blood samples were analyzed for cortisol, myeloperoxidase (MPO), and absolute neutrophil, lymphocyte, and monocyte counts. Creatine kinase (CK) was analyzed before and 24, 48, and 72 hours after the AHREP. Performance measures, including peak back squat isometric force and peak countermovement jump power were also analyzed. Nucleotide supplementation resulted in significant (p ≤ 0.05) decreases in cortisol and MPO immediately after the AHREP, and significantly lower CK values 24 hours later. The AHREP significantly affected leukocyte counts; however, no treatment effects were observed. Greater isometric force was observed immediately after AHREP and at 24 hours and 48 hours with nucleotide supplementation. Nucleotide supplementation seems to attenuate muscle damage, HPA axis and immune system activation, and performance decrements after heavy resistance exercise.

Effects of a whole body compression garment on recovery after a heavy resistance

This study aimed to investigate the effects of wearing a whole body compression garment on recovery from a typical heavy resistance training workout in resistance trained men and women. Fourteen men (mean ± SD: age, 23.0 ± 2.9 years) and fourteen women (mean ± SD: age 23.1 ± 2.2 years) who were highly resistance trained gave informed consent to participate in the study. A within-group (each subject acted as their own control), balanced, and randomized treatment design was used. Nutritional intakes, activity, and behavioral patterns (e.g., no pain medications, ice, or long showers over the 24 hours) were replicated 2 days before each test separated by 72 hours. An 6-exercise whole body heavy resistance exercise protocol using barbells (10 repetition of 3 sets at 70% of one- repetition maximum, 2.0 minute rest) was performed after which the subject showered and put on a specific whole body compression garment one designed for women and one for men (CG) or just wore his/her normal noncompression clothing (CON). Subjects were then tested after 24 hours. Dependent measures included sleep quality, vitality rating, resting fatigue rating, muscle soreness, muscle swelling via ultrasound, reaction movement times, bench throw power, countermovement vertical jump power, and serum concentrations of creatine kinase (CK) measured from a blood sample obtained via venipuncture of an arm vein. We observed significant (p≤ 0.05) differences between CG and CON conditions in both men and women for vitality (CG , CON), resting fatigue ratings (CG , CON), muscle soreness (CG , CON), ultrasound measure swelling (CG , CON), bench press throw (CG .CON), and CK (CG, CON). A whole body compression garment worn during the 24-hour recovery period after an intense heavy resistance training workout enhances various psychological, physiological, and a few performance markers of recovery compared with noncompressive control garment conditions. Wearing a CG appears to help in the recovery process after intense heavy resistance training in men and women.

Higher chronic psychological stress is associated with blunted affective responses to strenuous resistance exercise: RPE, pleasure, pain

The aim of this study was to determine whether mental stress moderates perceptions of muscular pain, exertion, pleasure and arousal during a bout of strenuous resistance exercise. Two hundred and ten undergraduate students recruited from resistance exercise classes were screened with the Perceived Stress Scale (PSS). Fifty-seven individuals (age = 20.1 ± 1.2 y) were invited to complete the Undergraduate Stress Questionnaire (USQ), a measure of life event stress, and fitness testing. They later performed a two-phase, acute heavy-resistance exercise protocol: first phase: 10-repetition maximum (RM) leg press test; second phase: six sets at 80–100% of 10-RM. During exercise, participants responded to the Feeling Scale (pleasure), Felt Arousal Scale, Omni-RPE and the Pain Intensity Scale. Affective responses and heart rate were analyzed with a hierarchical linear modeling (HLM) growth curve analysis. USQ moderated the trajectories of affective responses and heart rate during exercise. Higher stress (USQ) levels were significantly related to lower rise in RPE (time2, p = .002; time3, p < .001) and heart rate (time2, p < .001; time3, p < .001). USQ had a main effect on pleasure and arousal (p values < .001), in which higher levels of stress were related to less affect. Models using the PSS scale produced similar results. PSS, but not USQ, interacted with time to predict pain (time2, p = .048; time3, p = .024). Relationships held even after adjusting for covariates, such as depression. Future research should determine if differential responses to exercise by stress have implications for behavioral interventions and mental health outcomes.

TNF-α and TNFR1 responses to recovery therapies following acute resistance exercise.

The purpose of this investigation was to compare the effect of two commonly used therapeutic modalities (a) neuromuscular electrical stimulation (NMES) and (b) cold water immersion (CWI) on circulating tumor necrosis factor alpha (TNF-α) and monocyte TNF-α receptor (TNFR1) expression following intense acute resistance exercise and subsequent recovery. Thirty (n = 30) resistance trained men (22.5 ± 2.7 y) performed an acute heavy resistance exercise protocol on three consecutive days followed by one of three recovery methods (CON, NMES, and CWI). Circulating TNF-α levels were assayed and TNFR1 expression on CD14+ monocytes was measured by flow cytometry measured PRE, immediately post (IP), 30-min post (30M), 24 h post (24H), and 48 h post (48H) exercise. Circulating TNF-α was elevated at IP (p = 0.001) and 30M (p = 0.005) and decreased at 24H and 48H recovery from IP in CON (p = 0.015) and CWI (p = 0.011). TNF-α did not significantly decrease from IP during recovery in NMES. TNFR1 expression was elevated (p < 0.001) at 30M compared to PRE and all other time points. No significant differences between groups were observed in TNFR1 expression. During recovery (24H, 48H) from muscle damaging exercise, NMES treatment appears to prevent the decline in circulating TNF-α observed during recovery in those receiving no treatment or CWI.

Effects of β-Hydroxy-β-methylbutyrate Free Acid Ingestion and Resistance Exercise on the Acute Endocrine Response.

Objective. To examine the endocrine response to a bout of heavy resistance exercise following acute β-hydroxy-β-methylbutyrate free acid (HMB-FA) ingestion. Design. Twenty resistance trained men were randomized and consumed either 1 g of HMB-FA (BetaTor) or placebo (PL) 30 min prior to performing an acute heavy resistance exercise protocol. Blood was obtained before (PRE), immediately after (IP), and 30 min after exercise (30P). Circulating concentrations of testosterone, growth hormone (GH), insulin-like growth factor (IGF-1), and insulin were assayed. Data were analyzed with a repeated measures ANOVA and area under the curve (AUC) was analyzed by the trapezoidal rule. Results. The resistance exercise protocol resulted in significant elevations from PRE in testosterone (P < 0.01), GH (P < 0.01), and insulin (P = 0.05) at IP, with GH (P < 0.01) and insulin (P < 0.01) remaining elevated at 30P. A significant interaction was noted between groups in the plasma GH response at IP, which was significantly higher following HMB-FA compared to PL (P < 0.01). AUC analysis revealed an elevated GH and IGF-1 response in the HMB-FA group compared to PL. Conclusion. HMB-FA prior to resistance exercise augments the GH response to high volume resistance exercise compared to PL. These findings provide further support for the potential anabolic benefits associated with HMB supplementation.

Chronic Psychological Stress Impairs Recovery of Muscular Function and Somatic Sensations Over a 96-Hour Period

The primary aim of this study was to determine whether chronic mental stress moderates recovery of muscular function and somatic sensations: perceived energy, fatigue, and soreness, in a 4-day period after a bout of strenuous resistance exercise. Undergraduate resistance training students (n = 31; age, 20.26 ± 1.34 years) completed the Perceived Stress Scale and the Undergraduate Stress Questionnaire, a measure of life event stress. At a later visit, they performed an acute heavy-resistance exercise protocol (10 repetition maximum [RM] leg press test plus 6 sets: 80-100% of 10RM). Maximal isometric force (MIF), perceived energy, fatigue, and soreness were assessed in approximately 24-hour intervals after exercise. Recovery data were analyzed with hierarchical linear modeling growth curve analysis. Life event stress significantly moderated linear (p = 0.027) and squared (p = 0.031) recovery of MIF. This relationship held even when the model was adjusted for fitness, workload, and training experience. Perceived energy (p = 0.038), fatigue (p = 0.040), and soreness (p = 0.027) all were moderated by life stress. Mean perceived stress modulated linear and squared recovery of MIF (p < 0.001) and energy (p = 0.004) but not fatigue or soreness. In all analyses, higher stress was associated with worse recovery. Stress, whether assessed as life event stress or perceived stress, moderated the recovery trajectories of muscular function and somatic sensations in a 96-hour period after strenuous resistance exercise. Therefore, under conditions of inordinate stress, individuals may need to be more mindful about observing an appropriate length of recovery.

Ballistic exercise as a pre-activation stimulus: a review of the literature and practical applications.

Post-activation potentiation (PAP) refers to the acute enhancement of muscular function as a direct result of its contractile history. Protocols designed to elicit PAP have commonly employed heavy resistance exercise (HRE) as the pre-activation stimulus; however, a growing body of research suggests that low-load ballistic exercises (BE) may also provide an effective stimulus. The ability to elicit PAP without the need for heavy equipment would make it easier to utilise prior to competition. It is hypothesised that BE can induce PAP given the high recruitment of type II muscle fibres associated with its performance. The literature has reported augmentations in power performance typically ranging from 2 to 5 %. The performance effects of BE are modulated by loading, recovery and physical characteristics. Jumps performed with an additional loading, such as depth jumps or weighted jumps, appear to be the most effective activities for inducing PAP. Whilst the impact of recovery duration on subsequent performance requires further research, durations of 1-6 min have been prescribed successfully in multiple instances. The effect of strength and sex on the PAP response to BE is not yet clear. Direct comparisons of BE and HRE, to date, suggest a tendency for HRE protocols to be more effective; future research should consider that these strategies must be optimised in different ways. The role of acute augmentations in lower limb stiffness is proposed as an additional mechanism that may further explain the PAP response following BE. In summary, BE demonstrates the potential to enhance performance in power tasks such as jumps and sprints. This review provides the reader with some practical recommendations for the application of BE as a pre-activation stimulus.

The influence of age and exercise modality on growth hormone bioactivity in women

ObjectivePrior research has indicated that the loss of skeletal muscle mass and bone mineral density observed with aging is related to the prominent age-related decline in the concentration of serum growth hormone (GH). However, there is limited data on the effects of aging on GH responses to acute bouts of heavy resistance exercise (HRE) and aerobic exercise (AE). DesignThe present investigation examined the effects of a HRE protocol and an AE protocol on immunoreactive GH (IGH) and bioactive GH (BGH) in active young and old women. ResultsOlder women had a diminished serum IGH response to both the HRE and AE protocols compared to the younger women, however a similar response was not observed in serum BGH. Additionally, the HRE protocol elicited a greater BGH response than the AE protocol exclusively in the younger group. ConclusionsRegardless of exercise mode, aging induces an increase in growth hormone polymerization that specifically results in a loss of serum growth hormone immunoreactivity without a concurrent loss of serum growth hormone bioactivity. The greater BGH response to the HRE protocol found in the younger group can be attributed to an unknown serum factor of molecular weight between 30 and 55kD that either potentiated growth hormone bioactivity in response to HRE or inhibited growth hormone bioactivity in response to AE.

Acute anabolic response to β-hydroxy-β-methylbutyrate (HMB)-free acid supplementation following heavy resistance exercise

Background b-hydroxy-b-methylbutyrate (HMB), a metabolite of the amino acid leucine, has been shown to promote strength and lean muscle mass when supplemented in conjunction with resistance training. Recently, a new free-acid form of HMB has been shown to reach higher plasma concentrations in a shorter amount of time compared to the calcium-salt form. This higher bioavailability may rationalize acute supplementation with HMB-FA as a means to enhance the anabolic response resulting from heavy resistance training. The purpose of this study was to examine the effect of acute b-hydroxy-b-methylbutyrate-free acid (HMB-FA) on circulating concentrations of anabolic hormones following a heavy resistance exercise protocol. Methods Twenty resistance-trained men (22.8 ± 2.5 yrs, 177.6 ± 6.6cm, 83.4 ± 9.8kg) volunteered to participate in this study and were randomized into two groups [HMB-FA and placebo (PL)] and performed an acute, heavy resistance exercise protocol (four sets of up to 10 repetitions of the squat, dead lift, and split squat exercises). Supplementation included 1 g of HMB-FA or PL consumed 30min prior to exercise. Blood was sampled before (PRE), immediately post (IP), and 30 min post-exercise (30P). Circulating levels of testosterone (TEST), growth hormone (GH) and Insulin (INS) were assayed. A 2 x3 repeated measures ANOVA was used to analyze the data. Consent to publish the results was obtained from all participants. Results The resistance exercise protocol produced a significant time effect for an elevation in TEST (p<0.01), GH (p<0.01) and INS (p = 0.05) at IP with GH (p<0.01) and INS (p<0.01) remaining elevated at 30P. A group by time interaction was observed (p = 0.05) with plasma GH elevated in HMB-FA compared to PRE values (p< 0.01) at IP and 30P. There were no differences at any other time point with TEST or INS concentrations. Conclusion

Psychological Stress Impairs Short-Term Muscular Recovery from Resistance Exercise

The primary aim of this study was to determine whether chronic mental stress moderates recovery of muscular function, perceived energy, fatigue, and soreness in the first hour after a bout of strenuous resistance exercise. Thirty-one undergraduate resistance training students (age = 20.26 ± 1.34 yr) completed the Perceived Stress Scale and Undergraduate Stress Questionnaire (USQ; a measure of life event stress) and completed fitness testing. After 5 to 14 d of recovery, they performed an acute heavy-resistance exercise protocol (10-repetition maximum (RM) leg press test plus six sets: 80%-100% of 10 RM). Maximal isometric force (MIF) was assessed before exercise, after exercise, and at 20, 40, and 60 min postexercise. Participants also reported their levels of perceived energy, fatigue, and soreness. Recovery data were analyzed with hierarchical linear modeling growth curve analysis. Life event stress significantly moderated linear (P = 0.013) and squared (P = 0.05) recovery of MIF. This relationship held even when the model was adjusted for fitness, workload, and training experience. Likewise, perceived stress moderated linear recovery of MIF (P = 0.023). Neither USQ nor Perceived Stress Scale significantly moderated changes in energy, fatigue, or soreness. Life event stress and perceived stress both moderated the recovery of muscular function, but not psychological responses, in the first hour after strenuous resistance exercise.

Sex differences in creatine kinase after acute heavy resistance exercise on circulating granulocyte estradiol receptors

Previous research has shown reduced tissue disruption and inflammatory responses in women as compared to men following acute strenuous exercise. While the mechanism of this action is not known, estrogen may reduce the inflammatory response through its interaction with granulocytes. The purpose of this study was to determine if estrogen receptor β expression on granulocytes is related to sex differences in tissue disruption in response to an acute heavy resistance exercise protocol. Seven healthy, resistance-trained, eumenorrheic women (23 ± 3 years, 169 ± 9.1 cm, 66.4 ± 10.5 kg) and 8 healthy, resistance-trained men (25 ± 5 years, 178 ± 6.7 cm, 82.3 ± 9.33 kg) volunteered to participate in the study. Subjects performed an acute resistance exercise test consisting of six sets of five squats at 90% of the subject's one repetition maximum. Blood samples were obtained pre-, mid-, post-, and 1-, 6-, and 24-h postexercise. Blood samples were analyzed for 17-β-estradiol by ELISA, creatine kinase by colorimetric enzyme immunoassay, and estradiol receptors on circulating granulocytes through flow cytometry. Men had higher CK concentrations than women at baseline/control. Men had significantly higher CK concentrations at 24-h postexercise than women. No significant changes in estradiol β receptors were expressed on granulocytes after exercise or between sexes. While sex differences occur in CK activity in response to strenuous eccentric exercise, they may not be related to estradiol receptor β expression on granulocytes. Thus, although there are sex differences in CK expression following acute resistance exercise, the differences may not be attributable to estrogen receptor β expression on granulocytes.

Leukocyte β2-Adrenergic Receptor Expression in Response to Resistance Exercise

Epinephrine and norepinephrine mediate interactions between the neuroendocrine and the immune systems to alter immune cell activity. Although both systems respond to exercise stress, less is known about how they interact in response to such stress. The purpose of this investigation was to examine β2-adrenergic receptor (β2-ADR) expression on circulating leukocytes to an acute bout of resistance exercise in men and women. Resistance-trained men (n = 8; mean ± SD age = 24.63 ± 5.07 yr, body mass index = 26.09 ± 2.21 kg·m(-2)) and women (n = 7; age = 22.13 ± 3.09 yr, body mass index = 22.63 ± 2.03 kg·m(-2)) performed an acute resistance exercise protocol (six sets of five-repetition maximum heavy squats) and a control test (i.e., identical conditions with no exercise) in a balanced, randomized order. Using a within-subject design, β2-ADR expressions on circulating leukocytes were evaluated with flow cytometry, and plasma epinephrine and norepinephrine were evaluated with high-performance liquid chromatography. Plasma epinephrine and norepinephrine increased during the exercise bout and returned to baseline during recovery. β2-ADR expression on monocytes was elevated in anticipation of the exercise protocol. β2-ADR expression on monocytes and granulocytes decreased during the exercise. β2-ADR expression on lymphocytes was elevated during the recovery time points. In conclusion, β2-ADR expression on leukocyte subpopulations changes in response to acute heavy resistance exercise protocol. The present findings provide insights into the potential temporal interactions between the neuroendocrine and the immune systems in response to the physiological stress of acute heavy resistance exercise in men and women.

B2-Adrenergic Receptor Expression on Human Leukocytes in Response to Acute Heavy Resistance Exercise

Epinephrine and norepinephrine mediate interactions between the neuro-endocrine and the immune systems, to alter immune cell activity. While both systems respond to exercise stress, less in known about how they interact in response to such stress. PURPOSE: To examine B2-Adrenergic receptor (B2-ADR) expression on circulating leukocytes to an acute bout of resistance exercise in men and women. METHODS: Resistance trained men (mean ± SD (n=8) age: 23.28 ± 4.26 y; body mass index: 24.51 ± 2.61 kg/m2) and women ((n=7) age: 22.13 ± 3.09 y; body mass index: 22.63 ± 2.03 kg/m2) performed an acute resistance exercise protocol (6 sets of 5 RM heavy squats) and a control test (i.e., identical conditions with no exercise) in a balanced, randomized order. Using a within subject design, B2-Adrenergic receptor (B2-ADR) expression on circulating leukocytes were evaluated with flow cytometry and plasma epinephrine and norepinephrine were evaluated with high performance liquid chromatography. RESULTS: Plasma epinephrine and norepinephrine increased during the exercise bout and returned to baseline during recovery (p<0.05). B2-ADR expression on monocytes was elevated in anticipation of the exercise protocol (p<0.05). B2-ADR expression on monocytes and granulocytes decreased during the exercise (p<0.05). B2-ADR expression on lymphocytes was elevated during the recovery time points (p<0.05). CONCLUSION: B2-ADR expression on leukocyte subpopulations changes in response to acute heavy resistance exercise protocol. Present findings provide insights into the temporal interactions between the neuro-endocrine and the immune systems in response to the physiological stress of acute heavy resistance exercise in men and women.

Effects of a Whole Body Compression Garment on Markers of Recovery After a Heavy Resistance Workout in Men and Women

The primary purpose of this investigation was to evaluate the influence of a whole body compression garment on recovery from a typical heavy resistance training workout in resistance-trained men and women. Eleven men (mean +/- SD: age, 23.0 +/- 2.9 years) and 9 women (mean +/- SD: age 23.1 +/- 2.2 years) who were highly resistance trained gave informed consent to participate in the study. A within-group (each subject acted as their own control), balanced, and randomized treatment design was used. Nutritional intakes, activity, and behavioral patterns (e.g., no pain medications, ice, or long showers over the 24 hours) were replicated 2 days before each test separated by 72 hours. An 8-exercise whole body heavy resistance exercise protocol using barbells (3 sets of 8-10 repetition maximum, 2.0- to 2.5-minute rest) was performed after which the subject showered and put on a specific whole body compression garment one designed for women and one for men (CG) or just wore his/her normal noncompression clothing (CON). Subjects were then tested after 24 hours. Dependent measures included sleep quality, vitality rating, resting fatigue rating, muscle soreness, muscle swelling via ultrasound, reaction movement times, bench throw power, countermovement vertical jump power, and serum concentrations of creatine kinase (CK) measured from a blood sample obtained via venipuncture of an arm vein. We observed significant (p < or = 0.05) differences between CG and CON conditions in both men and women for vitality (CG > CON), resting fatigue ratings (CG < CON), muscle soreness (CG < CON), ultrasound measure swelling (CG < CON), bench press throw (CG > CON), and CK (CG < CON). A whole body compression garment worn during the 24-hour recovery period after an intense heavy resistance training workout enhances various psychological, physiological, and a few performance markers of recovery compared with noncompressive control garment conditions. The use of compression appears to help in the recovery process after an intense heavy resistance training workout in men and women.

Changes in power curve shapes as an indicator of fatigue during dynamic contractions

The purpose of this study was to analyze exercise-induced leg fatigue during a dynamic fatiguing task by examining the shapes of power vs. time curves through the combined use of several statistical methods: B-spline smoothing, functional principal components and (supervised and unsupervised) classification. In addition, granulometric size distributions were also computed to allow for comparison of curves coming from different subjects. Twelve physically active men participated in one acute heavy-resistance exercise protocol which consisted of five sets of 10 repetition maximum leg press with 120s of rest between sets. To obtain a smooth and accurate representation of the data, a basis of 180 B-splines was used. Functional principal component (FPC) analysis was used to find the dominant modes of variation in the curves. A multivariate cluster over the FPC scores and a k-nearest neighbor classification led to three interpretable groups corresponding to different levels of fatigue. Fatigue-induced changes in the shapes of the power curves were evident, in which curves progressively flatten and develop a second power peak. In a practical setting FPC analysis greatly reduces dimensionality and the use of granulometries allows for comparison of the curve shapes without distorting the time scale.In contrast to the present methodology, which considers each curve as a datum, classical statistical approaches using summary parameters of time series may lead to limited information about the impact of dynamic fatiguing protocols on kinematic and kinetic time-course changes in curve shapes.

The Acute Effects of Heavy Back Squats on Mechanical Variables During a Series of Bilateral Hops

The purpose of the present study was to investigate the acute effects of performing a heavy resistance exercise (HRE) protocol on the mechanical variables during a series of bilateral hops. In a block-randomized design, 10 strength trained men performed an HRE or a control treatment before performing 5 series of bilateral hops separated by 2 minutes of passive recovery. Each series of bilateral hops was performed for 15 seconds on a force platform with the subject hopping at a frequency of 2.0 Hz. From the vertical force trace, the vertical force during the countermovement phase of each hop, the negative displacement during the countermovement phase, and the vertical stiffness were calculated. The HRE treatment consisted of performing parallel back squats with 40, 50, 60, and 80% of each subject's 1-repetition maximum after a series of dynamic stretches. The control treatment consisted of the dynamic stretches only. No significant differences in any of the mechanical variables were reported after the 2 treatments (p > 0.05). There were no significant correlations between the absolute maximal strength values and the percent change in any of the mechanical variables after the 2 treatments. Despite the lack of significant changes reported for the group, there were some notable individual responses. It is possible that increases in vertical stiffness during bilateral hops can be achieved after an HRE protocol in certain individuals. However, practitioners should be aware of the specificity issues and the individual nature of the responses to such protocols.