EXPLOSIVE TRAINING

and jumps) also facilitate the incorpora- tion of the triple extension of the ankles, hips and knees, counter movements in both relatively slow (squat) and very explosive movements (power clean, snatch) and also dead-stop-start accelera- tions. These characteristics have a large potential to transfer into improved neuro- muscular efficiency which, in turn, have been shown to be maximally beneficial to performance in biomechanically similar movements (5). Not only does this type of movement reflect the joint/muscular recruitment patterns imposed during skill performance, but the requirements for strength, power and force development for such exercises are similar to those required in sports. For example, because technique is dependent upon appropriate force production, training the athlete’s ability to generate force is arguably the biggest training priority (factors that primarily

TECHNIQUE GUIDANCE

The double knee bend In both the snatch and the squat clean, pulling movements are used to raise the bar from the floor, up the front of the body, to a position where the athlete squats under the bar and catches it in an overhead (snatch) or in front of the neck (clean) position. In both of these lifts, the most efficient pulling technique has been observed over time to be the double knee bend. Not only does this introduce a sud- den forceful stretch-shortening cycle into the lift, but the unweighted position also reduces tension on the back (11).

Figures 1a,b,c show David Smith (GB Bobsleigh) performing a snatch lift. This sequence of photographs demonstrate clearly the three key positions associated with the execution of the double knee bend lift.

Start position The feet are flat on the floor, hips posi- tioned slightly higher than the knees, back is held straight and the athlete’s shoulders are positioned over, and in front of, the bar. The arms should be straight, with the elbows rotated outwards and pointing along the length of the bar.

The back should be held straight (with a normal lordotic curve in the lumber spine). This is aided by the shoulder blades being

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influence winning and losing) for the strength and conditioning coach. The importance of force generation is illustrat- ed by Newtons 2nd law (force = mass x acceleration). Acceleration is important as this results in a velocity: velocity is a vital component of power and is often a deter- mining factor in superior performance.

Rate of force development Another important characteristic that accompanies force generation is rate of force development (RFD). What is also very important to realise is that RFD can be associated with acceleration capabilities in athletes (6), and this can also be a determining factor in generating superior athletic performance. Most critical aspects of sports performance occur in very short time-frames (<250ms). If athletes can be trained to produce greater forces within that time frame, then greater accelera-

Figure 1a: The start position for the snatch lift

Figure 1b: The end of the first pull, with the bar level with the top of the knees

Figure 2a: Mike Favre demonstrates the start position for the squat clean. The annotated lines indicate the position of the trunk in relation to the bar and the ground (11,12).

pulled back towards each other (‘imagine holding a £5 note between them’) and the chest pushed out at the same time. Indeed, a coach standing in front of the player lifting should be able to see the whole of the chest from the front. The head should also be up at all times.

First pull Teaching the first pull phase of the lifts

Figure 2b: Mike Favre demonstrates the position of the trunk at the end of the first pull. Note that the angle between the trunk and the ground has not changed.

correctly can be the key to ensure that the double knee bend happens. With proper execution of the 1st Pull, the athlete is more likely to perform a double knee bend (11,12).

The importance of correctly executing the first pull is to get the bar moving with minimal energy expenditure, achieving an

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