I enjoy George Nassis’ blog because he simply posts abstracts from recent studies and allows readers to make their own inferences. I decided to do some of the same here.
Zadro, I, Sepulcri, L, Lazzer, S, Fregolent, R, and Zamparo, P. (2011). A protocol of intermittent exercise (shuttle runs) to train young basketball players. Journal of Strength & Conditioning Research, 25(6): 1767-1773.
The purpose of this study was to set up a protocol of intermittent exercise to train young basketball players. Twenty-one players were asked to complete (a) an incremental test to determine maximal oxygen uptake (V̇O2max), the speed at the ventilatory threshold (vthr) and the energy cost of “linear” running (Cr) and (b) an intermittent test composed of 10 shuttle runs of 10-second duration and 30-seconds of recovery (total duration: about 6 minutes). The exercise intensity (the running speed, vi) was set at 130% ofvthr. During the intermittent tests, oxygen uptake (V̇O2) and blood lactate concentration (Lab) were measured. The average pretraining V̇O2 calculated for a single bout (131 ± 9 ml·min−1kg−1) was about 2.4 times greater than the subjects’ measured V̇O2max (54.7 ± 4.6 ml·min−1·kg−1). The net energy cost of running (9.2 ± 0.9 J·m−1·kg−1) was about 2.4 times higher than that measured at constant “linear” speed (3.9 ± 0.3 J·m−1·kg−1). The intermittent test was repeated after 7 weeks of training: 9 subjects (control group [CG]) maintained their traditional training schedule, whereas for 12 subjects (experimental group [EG]) part of the training was replaced by intermittent exercise (the same shuttle test as described above). After training, the V̇O2 measured during the intermittent test was significantly reduced (p < 0.05) in both groups (−10.9% in EG and − 4.6 in CG %), whereas Lab decreased significantly only for EG (−31.5%). These data suggest that this training protocol is effective in reducing lactate accumulation in young basketball players.
Zody, A; Rossi, S; McMillan, J; Buckley, T. (2011). Under Recovery and Drop Jump Characteristics During a Collegiate Basketball Season in Female Basketball Players. Journal of Strength & Conditioning Research, 25.
Collegiate basketball is a demanding sport that requires extensive in-season training which can sometimes lead to under- recovery potentially resulting in poor performance, injury, or illness. To minimize the risk of this occurring and to promote optimal performance across the season, frequent testing may be necessary.
PURPOSE: The purpose of this study was to examine the performance characteristics and in-season recovery of female basketball players using drop jump characteristics: contact time (CT), flight time (FT), relative peak force (RPF), rate of force development (RFD), jump height (JH), reactive strength index (RSI), and recovery-stress states (RESTQ-Sport).
METHODS: Participants were 14 NCAA Division-1 female basketball players (age = 19.29 +/- 1.54 years, mass = 76.09 +/- 14.09kg, height = 178.70 +/- 6.3cm). During each test session, participants filled out the REST-Q Sport questionnaire, which assesses self-perceived stress and recovery, prior to performing two drop jumps. The jump trials were performed with an arm swing from a height of 30cm onto two 400x600mm forceplates (AMTI, Model OR-6, Watertown, MA) with data sampled at 1000 Hz. Participants were assessed on three occasions (T1, T2, T3) over the month of preseason training with approximately two weeks between test dates and on four occasions (T4, T5, T6, T7) throughout the season. Total recovery stress score, global recovery score, and global stress score were also calculated throughout the season.
RESULTS: With the significance level set at p<0.05, repeated measures ANOVA revealed significant differences in FT (p = 0.017), JH (p = .000), and RSI (p = 0.018) across time. Significant differences in FT were found between T1 (.453 +/- 0.03s) to T3 (.436 +/- 0.04s, p = 0.043) and to T4 (.432 +/- .02, p = 0.035). There were significant differences in JH between T1 (.254 +/- 0.03m) to T3 (.233 +/- 0.04m, p = 0.021), T4 (.230 +/- .02, p = 0.035), and to T7 (.230 +/- .02m, p = .000). RSI was found to be significant between T1 (.651 +/- .25) to T3 (.607 +/- .20, p = 0.045) and to T4 (.559 +/- .018, p = 0.027). Significant differences were also observed in total- recovery stress score (p = 0.001), global recovery (p = 0.001), and global stress scores (p = 0.01). Total-recovery stress was significant between T1 (4.68 +/- 13.12) to T2 (.447 +/- 11.52, p = 0.023), T4 (-1.91 +/- 11.80, p = 0.010), T5 (-11.30 +/- 21.30, p = 0.007), and to T6 (-5.73 +/- 8.58, p = 0.005). Global recovery was significant between T1 (28.82 +/- 9.38) to T4 (23.13 +/- 7.76, p = 0.013), T5 (21.02 +/- 9.53, p = 0.012), and to T6 (22.41 +/- 6.06, p = 0.005). Global stress was significant between T1 (24.14 +/- 7.21) to T5 (32.32 +/- 12.99, p = 0.015).
CONCLUSIONS: The results show drop jump characteristics declined throughout the course of a basketball season. The abnormally high stress scores and low recovery scores may suggest a hindrance in female basketball players’ ability to perform well at the end of the season.
PRACTICAL APPLICATIONS: The data justifies using simple performance and psychological tests to help strength and conditioning coaches monitor information regarding stress and recovery of female collegiate athletes during in-season training.