When deciding on the athlete monitoring tools to use with your athletes, the first question one should ask is “What do I want to achieve through athlete monitoring?” Quite commonly, the answer is to maximise the positive effects (eg, fitness, readiness and performance) and minimise the negative effects (eg, excessive fatigue, injury and illness) of training. Once practitioners know the reasons for athlete monitoring, appropriate tools can be chosen in order to answer the athlete monitoring question.

We aimed to improve the physical capacity of a top-level elite football team during its pre-season by implementing a maximal strength and high-intensity endurance training program. 21 first league elite football players (20–31 yrs, height 171–194 cm, mass 58.8–88.1 kg) having recently participated in the UEFA Champions’ League, took part in the study. Aerobic interval-training at 90–95% of maximal heart rate and half-squats strength training with maximum loads in 4 repetitions×4 sets were performed concurrently twice a week for 8 weeks. The players were not familiar with maximal strength training as part of their regular program. Maximal oxygen uptake (VO_2max) increased 8.6% (1.7–16.6) (p<0.001), from 60.5 (51.7–67.1) to 65.7 (58.0–74.5) mL · kg⁻¹ · min⁻¹ whereas half-squat one repetition maximum increased 51.7% (13.3–135.3) (p<0.001), from 116 (85–150) to 176 (160–210) kg. The 10-m sprint time also improved by 0.06 s (0.02–0.16) (p<0.001); while counter movement jump improved 3.0 cm (0.1–6.2) (p<0.001), following the training program. The concurrent strength and endurance training program together with regular football training resulted in considerable improvement of the players’ physical capacity and so may be successfully introduced to elite football players.

Injuries to lower limb muscles are common among football players. Localized bioimpedance analysis (BIA) utilizes electrical measurements to assess soft tissue hydration and cell membrane integrity non-invasively. This study reports the effects of the severity of muscle injury and recovery on BIA variables. We made serial tetra-polar, phase-sensitive 50 kHz localized BIA measurements of quadriceps, hamstring and calf muscles of three male football players before and after injury and during recovery until return-to-play, to determine changes in BIA variables (resistance (R), reactance (Xc) and phase angle (PA)) in different degrees of muscle injury. Compared to non-injury values, R, Xc and PA decreased with increasing muscle injury severity: grade III (23.1%, 45.1% and 27.6%), grade II (20.6%, 31.6% and 13.3%) and grade I (11.9%, 23.5% and 12.1%). These findings indicate that decreases in R reflect localized fluid accumulation, and reductions in Xc and PA highlight disruption of cellular membrane integrity and injury. Localized BIA measurements of muscle groups enable the practical detection of soft tissue injury and its severity.