Biathlon standing shooting performance, shooting technical components and postural balance at rest and during a race simulation

Abstract

Stability of hold and postural balance have been reported to be related to standing shooting performance, and to differentiate between different experience levels of biathletes. Recently, ability to minimize the movement of the rifle during the triggering phase has been suggested to be important. Race analyses have reported men to be slightly faster in their shooting than women. The purpose of this thesis was to study factors determining biathlon standing shooting performance at rest and during a race simulation, and differences in them between genders and age groups.

Male and female biathletes (n=23) fired 8x5 standing shots at rest (REST) and 2x5 shots during a race simulation of 2x5 min at 95% of maximal heart rate (RACE). Mean values in both conditions were calculated for shooting performance (SP_hit%, hit/all shots; SP_dist, distance from the center of the target), horizontal (DevX) and vertical (DevY) stability of hold (standard deviation of the aiming point 0-0.6 s before the shot), aiming accuracy (COG, mean distance of the aiming point 0-0.6 s before the shot), cleanness of triggering (ATV, distance travelled by the aiming point 0-0.2 s before the shot), timing of triggering (TIRE, time period when the mean location of the aiming point is closest to the center of the target: 0-0.2 s before the shot = 3, 0.2-0.4 s = 2, 0.4-0.6 s = 1), postural balance (standard deviation of the center of pressure location 0-0.6 s before the shot) of the whole body in shooting (SDY) and cross-shooting (SDX) direction, postural balance of each leg separately (SD*_F, front; SD*_R, rear), and weight distribution (% of weight on front leg). Subjects were examined as a whole group, and as further divided into subgroups by gender (M, men, n = 12; W, women, n = 11) and age (SEN, >20 years old, n = 13; JUN, <20 years old, n = 10).

SP_hit%, SP_dist, DevY, DevX, COG and ATV decreased from REST to RACE, accompanied by a decrease in postural balance. ATV, DevY, COG and SDY_R and were the most important components related to SP_dist both at REST (ATV r=0.75, p<0.001; DevY r=0.57, p<0.01; COG r=0.52, p<0.05; SDY_R r=0.63, p<0.01) and in RACE (ATV r=0.63, p<0.01; DevY r=0.56, p<0.01; COG r=0.45, p<0.01; SDY_R r=0.58, p<0.01). Postural balance, especially that of rear leg in shooting direction, was also related to ATV, DevY and COG both at REST and in RACE. Lower shooting technical level, especially worse DevY and COG, were related to higher TIRE both at REST (DevY r=0.45, p<0.05; COG r=0.82, p<0.001) and in RACE (DevY r=0.65, p<0.01; COG r=0.78, p<0.001). Decreases in rear leg balance were related to decreases in SP_hit%. Decreases in DevY, COG and postural balance were related to increases in TIRE. Weight distribution was related to SDY_R at REST (r=0.47, p<0.05). Both at REST and in RACE, W demonstrated better ATV (REST 48 ± 4 mm vs 61 ± 9 mm, p<0.001; RACE 62 ± 10 mm vs 76 ± 11 mm, p<0.01), DevY (16 ± 4 mm vs 22 ± 7 mm, p<0.05; 20 ± 4 mm vs 27 ± 8 mm, p<0.01), COG (28 ± 9 mm vs 44 ± 14 mm, p<0.01; 35 ± 12 mm vs 53 ± 17 mm, p<0.01) and SDY_R (0.18 ± 0.04 mm vs 0.26 ± 0.08 mm, p<0.05; 0.24 ± 0.06 mm vs 0.35 ± 0.09 mm, p<0.01) than M, whereas M demonstrated higher TIRE in RACE (2.72 ± 0.26 vs 2.47 ± 0.21, p < 0.05). Despite better shooting technical level in both, SP_hit% and SP_dist were better in W at REST only (both p<0.05). In M, all postural balance variables decreased from REST to RACE (all p<0.05), whereas in W only SDY and SDY_R decreased (both p<0.05). At REST, SEN demonstrated better SP_hit% (92 ± 6% vs 82 ± 8%, p<0.01), SP_dist (33 ± 4 vs 41 ± 7 mm, p<0.01), DevY (16 ± 5 mm vs 23 ± 6 mm, p<0.01), ATV (51 ± 7 mm vs 60 ± 10 mm, p<0.05) and SDY (0.62 ± 0.15 mm vs 0.78 ± 0.17 mm, p<0.05) than JUN. In RACE, only DevY (20 ± 5 mm vs 28 ± 8 mm, p<0.01) and SDY_R (0.25 ± 0.06 mm vs 0.36 ± 0.10 mm, p<0.05) were better in SEN. Five out of six postural balance variables decreased in JUN (all p<0.05), whereas only SDY and SDY_R decreased in SEN (both p<0.05).

These findings indicate, that athletes should focus on vertical stability of hold, cleanness of triggering and aiming accuracy in their shooting technical training. For a controlled aiming process, especially vertical stability of hold and aiming accuracy should be at a good level, whereas cleanness of triggering plays a major role in the outcome of the shot. A stable posture is a prerequisite for good shooting performance, and athletes should avoid putting too much weight on their front leg. To improve shooting technical routines and postural control, sport-specific exercise sessions under variable conditions and with varying tasks are recommended. Lastly, shooting technical routines (rhythm, breathing, aiming) should be similar in every training session, regardless of physical training intensity.