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http://www.youtube.com/watch?v=ePwvZoXZu20
the dunk is tight, but click through to see trevor booker's reaction in the vine here: http://deadspin.com/the-incredible-dunk-is-only-the-first-half-of-this-high-1749266633.
lolololol
The use of inter-repetition rest within a set (IRR) has been reported to
attenuate the decline in power performance when compared with continuous
repetition set configurations. However, the effect of IRR duration between
single squat jump repetitions is unknown. This knowledge might be
advantageous to optimize power development. Twenty male subjects
completed four squat jumps at 20% of a 1 RM back squat under four different
protocol conditions: TR0 = no IRR between repetitions (reps), P15 = 15
seconds(s) between reps, P30 = 30 s between reps and P45 = 45 s between
reps. Peak force (PF), peak velocity (PV), and peak power (PP) were
measured for each trial. Significant increases (P < 0.05) in PP and PV were
noted during P30 from Rep (R)1 to R3 and R4, and P45 R2 to R4. Comparison
of likewise repetitions across conditions show that subjects were able to
produce superior PP and PV efforts during R4 across all IRR conditions
compared to with TR (Figures 6-8). This was statistically significant during P45
for PV and PP (R4 PP P = 0.004, R4 PV P = 0.002). Mean NET values for the
four conditions show a linear increase in PP, PF, and PV with an increase in
IRR (although non-significant). In agreement with Hansen et al. (19) and
Hardee et al. (20-22), the results demonstrate a positive influence of IRR to
enhance power output. Strength and Conditioning Coaches could use IRR to
accelerate the learning process and increase power during training. Of the
four conditions explored, an IRR of 45 s appears optimal to maximize power
output during a squat jump.
Abstract
[Purpose] The purpose of this study was to investigate the effects of bodyweight-based exercise with blood flow restriction on isokinetic muscular function and thigh circumference in college students. [Subjects and Methods] The subjects were 17 college students who were recruited and randomly assigned to bodyweight-based exercise with blood flow restriction and bodyweight-based exercise groups. Participants performed front lunges and squats at ratings of perceived exertion of 11–13 three times a week during a 6-week training period. The peak torque/ body weight (%) of the knee flexor and extensor was measured using a HUMAC NORM System (Cybex 770-NORM®, Cybex International, Medway, MA, USA), and the circumference of the thigh was measured. PASW Statistics was used for data analysis. [Results] There were significant differences in the peak torque/ body weight (%) of the flexors in both thighs (at 180°/sec) after bodyweight-based exercise with blood flow restriction. In addition, the circumference changes in both thighs were significant after bodyweight-based exercise with blood flow restriction and between the two groups. [Conclusion] This study suggests that bodyweight-based exercise with blood flow restriction may be an effective method to improve the muscle power and hypertrophy of the lower extremity in a clinical setting.
Abstract
During prolonged exercise, fluid and salt losses through sweating reduce plasma volume which leads to heart rate drift in association with hyperthermia and reductions in performance. Oral rehydration with water reduces the loss of plasma volume and lessens heart rate drift and hyperthermia. Moreover, the inclusion of sodium in the rehydration solution to levels that double those in sweat (i.e., around 90 mmol/l Na+) restores plasma volume when ingested during exercise, and expands plasma volume if ingested pre-exercise. Pre-exercise salt and fluid ingestion with the intention of expanding plasma volume has received an increasing amount of attention in the literature in recent years. In four studies, pre-exercise salt and fluid ingestion improved performance, measured as time to exhaustion, either during exercise in a thermoneutral or in a hot environment. While in a hot environment, the performance improvements were linked to lowering of core temperatures and heart rate, the reasons for the improved performance in a thermoneutral environment remain unclear. However, when ingesting pre-exercise saline solutions above 0.9% (i.e., > 164 mmol/l Na+), osmolality and plasma sodium increase and core temperature remain at dehydration levels. Thus, too much salt counteracts the beneficial effects of plasma volume expansion on heat dissipation and hence in performance. In summary, the available literature suggests that pre-exercise saline ingestion with concentrations not over 164 mmol/l Na+ is an ergogenic aid for subsequent prolonged exercise in a warm or thermoneutral environment.
Abstract
Purpose
Dietary supplements inducing alkalosis have been shown to be ergogenic during intense endurance exercise in temperate environments, but there is lack of data regarding the efficacy of these substances in the heat. This study aimed to investigate the effect of sodium citrate (CIT) ingestion on 5,000-m running performance in a warm environment.
Methods
Sixteen non-heat-acclimated endurance-trained males (age 25.8 ± 4.4 years, VO2peak 56.9 ± 4.7 mL kg min) completed two 5,000-m self-paced treadmill runs with preceding CIT or placebo (wheat flour; PLC) ingestion in a double-blind, randomized, crossover manner in a climatic chamber (air temperature 32 °C, relative humidity 50 %).
Results
CIT ingestion (500 mg kg−1 body mass) compared to PLC induced increases in water retention, body mass and plasma volume (P < 0.05). Pre- and post-exercise blood HCO3 − concentration, base excess and pH were higher (P < 0.001) in CIT compared to PLC trial. Rectal temperature, body heat storage, heat storage rate, heart rate and 5,000-m running time (18.92 ± 2.05 min in CIT, 19.11 ± 2.38 min in PLC; 66 % likelihood of benefit, d = –0.09) were similar (P > 0.05) in the two trials. Post-exercise blood lactate concentration was higher (P < 0.001) in CIT (11.05 ± 3.22 mmol L−1) compared to PLC trial (8.22 ± 2.64 mmol L−1). Ratings of perceived exertion, fatigue and thermal sensation did not differ in the two trials (P > 0.05).
Conclusion
Acute CIT ingestion induces alkalosis, water retention, plasma volume expansion and an increase in post-exercise blood lactate concentration, but does not improve 5,000-m running performance in a warm environment in non-heat-acclimated endurance-trained males.