A comparison of foot and ankle biomechanics during running drills and distance running

The aim of this study was to compare the foot-ankle joint mechanics of running drills and running. Seventeen long-distance runners performed five popular running drills (A-skip, B-skip, Bounding, Heel flicks, Straight leg running) and a run at 3.88 m/s. Kinematics, kinetics and power values were calculated for the ankle, midtarsal (MT) and metatarsophalangeal (MP) joints. Electromyographic activity was recorded for the soleus, gastrocnemius medialis, lateralis and abductor hallucis muscle. The A-skip, the B-skip and the Heel flicks induced a smaller ankle (p < 0.001, ŋ2 = 0.41), MT (p < 0.001, ŋ2 = 0.43) and MP (p < 0.001, ŋ2 = 0.47) dorsiflexion peak than running. No difference was found between the running drills and running for ankle, MT and MP moment. The Bounding induces a higher positive ankle power than running (diff: 5.5 ± 7.5 J/kg, p = 0.014, d = 1.05). The A-skip (diff: 2.8 ± 2.9 J/kg, p < 0.001, d = 1.5) and the B-skip (diff: 2.7 ± 2.1 J/kg, p < 0.001, d = 1.4) induce a smaller MT positive power than running. This study offers an analysis of the mechanical behaviour of the foot-ankle complex to help track and field coaches select their running drills in an evidence-based manner.

Effects of High-Intensity Warm-Up on 5000-Meter Performance Time in Trained Long-Distance Runners

Warm-up protocols with high intensities before continuous running provide potential benefits for middle-distance runners. Nevertheless, the effect of high-intensity warm-ups on long-distance runners remains unclear. The purpose of this study was to verify the effect of a high-intensity warm-up protocol on 5000 m performance in trained runners. Thirteen male runners (34 ± 10 years, 62 ± 6 kg, 62.7 ± 5.5 ml/kg/min) performed two 5000 m time trials, preceded by two different warm-ups. One high-intensity warm up (HIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (100% of the running intensity) and one low-intensity warm up (LIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (70% of the running intensity)), where the running intensities were calculated using the results obtained in the Cooper test. Physiological and metabolic responses, and endurance running performance parameters, were evaluated by the Counter Movement Jump (CMJ), running rating of perceived exertion (RPE), blood lactate concentration (BLa), and performance running. Total time for the 5000 m was lower using HIWU when compared to LIWU (1141.4 ± 110.4 s vs. 1147.8 ± 111.0 s; p = 0.03; Hedges' g = 0.66). The HIWU warm-up led to an improvement in pacing strategy during the time trial. After warm-up protocols, the performance on the CMJ was improved only when applying HIWU (p = 0.008). Post warm-up BLa was significantly higher for HIWU vs. LIWU (3.5 ± 1.0 mmol·L-1 vs. 2.3 ± 1.0 mmol·L-1; p = 0.02), with similar behavior for the RPE (p = 0.002), internal load of the session (p = 0.03). The study showed that a high-intensity warm-up protocol can improve performance in the 5000 m in trained endurance runners.

Acute Effect of Upper and Lower Body Postactivation Exercises on Shot Put Performance

Kontou, EI, Berberidou, FT, Pilianidis, TC, Mantzouranis, NI, and Methenitis, SK. Acute effect of upper and lower body postactivation exercises on shot put performance. J Strength Cond Res 32(4): 970-982, 2018-The purpose of this study was to investigate the effect of different types of upper and lower' extremities exercises on acute increase of shot put performance, in moderate experienced throwers. Eight (n = 8) males and 9 (n = 9) female throwers participated in this study. Their bench press and squat maximum strength were measured while their shot put performance from power position was evaluated before and after 4 interventions: (a) plyometric push-ups (Plyo), (b) 6 s isometric push-ups (Iso), (c) 3 countermovement jumps (CMJs) and (d) 10 reps. of skipping (Skip). Interventions were performed in counterbalanced order with a 48-hour interval. Significant increase (p < 0.05) of shot put performances was observed after Plyo, Iso, and CMJ (range: 2.30 ± 1.82%-5.72 ± 4.32%). In addition, Iso induced the highest increase while Skip did not induce any improvement of throwing performance. The highest increases were recorded in men's performance after CMJ (5.72 ± 4.32%) while in women's performance after Iso (3.59 ± 2.7%). Javelin and discus throwers increase higher their performance after CMJs while shot putters after Iso. Significant correlations were found between training experience, maximum/relative strength, shot put performance and increase of throwing performance (%) after the interventions (r: 0.519-0.991, p < 0.05). Percentage increase of performance between Iso and Plyo have negative correlations (r: -0.569, p < 0.05) in contrast of those between Skip and CMJ (r: 0.710, p < 0.05). These results suggest that upper or lower body postactivation interventions may acutely increase the throwing performance. However, experience and strength are significant determinant of this increase.