Effects of familiarization on reliability of muscle-activation and gross efficiency in adolescents and adults

Figures & data

Figure 1. Metabolic power (MP; W) at an external power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Figure 2. External power output (PO; W) at 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Figure 3. Gross efficiency (GE%) at a power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Note: † = Significantly different to test l for that group.

Figure 4. Cadence (rev·min⁻¹) at an external power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Figure 5. Respiratory exchange ratio (RER) at an external power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Figure 6. EMG root mean square of the vastus lateralis (VL-EMG-rms [%]) at a power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Note: † = Significantly different to test l for that group.

Figure 7. EMG root mean square of the biceps femoris (BF-EMG-rms [%]) at a power output of 50% PO_peak across tests 1, 2 and 3 among adult (n = 9) and adolescent cyclists (n = 9).

Note: † = Significantly different to test l for that group.

Table 1. Reliability of GE, VL-EMG-rms (%), BF-EMG-rms (%) among adult (n = 9) and adolescent cyclists (n = 9)

		Adults (n = 9)			Adolescents (n = 9)
		Between-test differences			Between-test differences
		1 and 2	2 and 3	1 and 3	1 and 2	2 and 3	1 and 3
GE (%)	95% LoA	−0.51 ± 1.69	0.21 ± 2.45	−0.31 ± 2.41	1.9 ± 1.06^†	0.45 ± 2.11	2.40 ± 2.12^†
	CV% ± 95% CI	2.6 ± 1.2^*	2.9 ± 1.9	2.9 ± 1.7^*	6.8 ± 1.4	2.6 ± 1.9	8.3 ± 2.6
VL-EMG-rms (%)	95% LoA	−4.0 ± 17.5	0.3 ± 17.7	−4.2 ± 13.7	−9.5 ± 16.5^†	−5.6 ± 22.7	−15.0 ± 19.8^†
	CV% ± 95% CI	6.1 ± 3.4	6.3 ± 2.2	5.2 ± 2.7^*	8.4 ± 4.4	8.9 ± 4.6	12.2 ± 6.6
BF-EMG-rms (%)	95% LoA	1.3 ± 11.6	2.6 ± 19.7	3.9 ± 16.9	−12.7 ± 19.8^†	1.0 ± 27.6	−11.7 ± 23.3^†
	CV% ± 95% CI	4.3 ± 2.0^*	7.4 ± 2.8	6.4 ± 3.4	12.5 ± 7.3	11.5 ± 5.6	12.2 ± 6.5

Notes: Based on a power output at 50%PO_peak; CV = coefficient of variation; LoA = limits of agreement; EMG-rms (%) = electromyographic root mean square for vastus lateralis (VL) or biceps femoris (BF).

^† Significant difference between tests.

^* Significantly different CV% to adolescents within that between-test comparison.

Table 2. The relationship (r-values) between the inter-test differences of GE and inter-test differences EMG-rms of the vastus lateralis and biceps femoris among adults (n = 9) and adolescents (n = 9)

	Test 1 and Test 2 differences		Test 2 and Test 3 differences
	(GE diff vs. VL-EMG-rms diff)	(GE diff vs. BF-EMG-rms diff)	(GE diff vs. VL-EMG-rms diff)	(GE diff vs. BF-EMG-rms diff)
Adults (n = 9)	0.11	−0.09	−0.45	0.21
Adolescents (n = 9)	−0.36	−0.08	−0.27	0.17

Notes: Differences = the change between test 1 and 2 or 2 and 3; BF = biceps femoris; VL = vastus lateralis.