Table 4. Effects of load carriage, conventional endurance exercise, and essential amino acid supplementation on surrogate markers of muscle damage and muscle soreness during recovery.

	Baseline	15-min PE	195-min PE	Effect
Muscle Soreness (%)
Deltoids				M x T
LC-EAA	n/a	30.6 ± 31.3 †	3.2 ± 5.6*
LC-CON	n/a	28.5 ± 26.7 †	8.9 ± 16.1*
CE-EAA	n/a	1.9 ± 3.6	0.7 ± 0.8
CE-CON	n/a	3.8 ± 6.6	1.1 ± 1.9
Quadriceps				M, T
LC-EAA	n/a	14.5 ± 8.9	9.2 ± 12.9
LC-CON	n/a	20.1 ± 16.2	7.2 ± 6.0
CE-EAA	n/a	33.2 ± 28.4	18.4 ± 26.6
CE-CON	n/a	31.0 ± 23.8	20.7 ± 19.0
Gluteus				M x T
LC-EAA	n/a	5.2 ± 8.5 †	2.7 ± 3.8
LC-CON	n/a	12.2 ± 21.9 †	3.6 ± 4.3
CE-EAA	n/a	35.4 ± 25.8	7.2 ± 7.3*
CE-CON	n/a	26.5 ± 20.4	1.8 ± 2.4*
Gastrocnemius/Soleus
LC-EAA	n/a	23.9 ± 23.5	9.4 ± 14.3	NS
LC-CON	n/a	9.8 ± 12.3	6.3 ± 7.6
CE-EAA	n/a	14.2 ± 14.8	6.3 ± 11.2
CE-CON	n/a	16.0 ± 13.3	5.9 ± 14.9
Muscle Damage
Creatine Kinase
LC-EAA	202.1 ± 157.3	n/a	272.0 ± 85.9*	M x T
LC-CON	209.7 ± 197.5	n/a	269.1 ± 162.5*
CE-EAA	175.0 ± 169.6	n/a	248.1 ± 169.8*
CE-CON	178.5 ± 122.1	n/a	275.2 ± 195.6*
Lactate Dehydrogenase
LC-EAA	134.8 ± 43.3	n/a	140.3 ± 22.6	T
LC-CON	134.3 ± 27.5	n/a	150.8 ± 22.0
CE-EAA	126.7 ± 21.5	n/a	136.4 ± 25.4
CE-CON	121.5 ± 29.5	n/a	137.8 ± 21.2
Myoglobin
LC-EAA	29.8 5.4	n/a	68.5 25.4	M
LC-CON	28.9 11.6	n/a	109.3 85.9
CE-EAA	24.8 8.2	n/a	56.4 29.3
CE-CON	25.3 6.0	n/a	58.2 21.9

Data are mean ± SD, n = 10 per group. CE, conventional endurance exercise; LC, load carriage; CON, control; and EAA, essential amino acids; PE, post-exercise. Mode x time (M x T) interaction for deltoids, gluteus, and creatine kinase. Mode (M) and time (T) main effects for quadriceps, lactate dehydrogenase, and myoglobin. M and T effects indicate overall mean difference between modes and time, P < 0.05.

*Different from baseline (or 15-min PE) within mode and

^†corresponding time point for CE, M x T, P < 0.05.